PRESSURISED: 063 – Bioluminescent Symbiosis with Margaret McFall-Ngai - The Deep-Sea Podcast

Episode Transcript
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Speaker: You're on a ride with the dauntless. (00:02):
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Speaker: The hadal zone express. (00:05):
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Speaker: Hello and welcome to the Deep Sea podcast. (00:08):
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Speaker: Pressurized a short, punchy (00:10):
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Speaker: version of our main feed that (00:12):
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Speaker: gets right to the scientific (00:14):
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Speaker: point. (00:15):
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Speaker: If you like what you hear, you'd like to hear the full episode. (00:15):
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Speaker: You can find it in the same feed. (00:18):
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Speaker: And now, to get right to the (00:19):
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Speaker: point for this month's (00:21):
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Speaker: interview, I tracked down (00:23):
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Speaker: Margaret Mcfall-ngai. (00:25):
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Speaker: I read about her work actually (00:27):
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Speaker: in I Contain Multitudes by Ed (00:29):
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Speaker: Young. (00:31):
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Speaker: Really nice bit of pop sci writing about our relationship (00:32):
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Speaker: with the microbiome. (00:36):
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Speaker: And that's how I became aware of (00:37):
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Speaker: Margaret's work, which for the (00:39):
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Speaker: last thirty years has focused on (00:41):
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Speaker: the symbiotic relationship (00:43):
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Speaker: between a little bobtail squid (00:45):
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Speaker: and the bioluminescent bacteria (00:47):
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Speaker: that allow them to do their (00:50):
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Speaker: countershading. (00:51):
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Speaker: We can't do this kind of really involved experimentation on the (00:52):
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Speaker: deep sea animals. (00:56):
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Speaker: So I thought this was a really (00:57):
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Speaker: nice analog to try and look into (00:58):
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Speaker: how some of these relationships (01:00):
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Speaker: with producing light could have (01:01):
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Speaker: evolved. (01:03):
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Speaker: We're lucky to be joined by (01:14):
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Speaker: Doctor Margaret Mcfall-ngai, (01:16):
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Speaker: animal physiologist and (01:18):
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Speaker: biochemist, and she is a staff (01:19):
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Speaker: researcher at the Carnegie (01:21):
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Speaker: Institute in the Science (01:22):
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Speaker: Division of Biosphere Science (01:24):
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Speaker: and Engineering, with her lab (01:26):
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Speaker: stationed at the California (01:27):
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Speaker: Institute of Technology in the (01:28):
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Speaker: Biology and Biochemical (01:30):
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Speaker: Engineering Department. (01:32):
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Speaker: Her work grabbed me because it really explores the nuanced (01:33):
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Speaker: relationship between animals and light producing bacteria in the (01:38):
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Speaker: form of bioluminescence. (01:43):
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Speaker: So even though her work doesn't (01:44):
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Speaker: focus on the deep sea, it is (01:45):
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Speaker: really hard to study these kind (01:47):
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Speaker: of nuanced relationships in the (01:48):
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Speaker: deep sea. (01:50):
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Speaker: I'm sure we're going to get there, but we don't have the (01:50):
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Speaker: technology right now. (01:53):
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Speaker: And so this is a great animal model. (01:54):
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Speaker: Thanks for joining us, Margaret. (01:56):
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Speaker: Oh, you're most welcome. (01:57):
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Speaker: I'm delighted. (01:59):
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Speaker: Give us an overview of what you've been studying. (01:59):
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Speaker: Sure. (02:02):
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Speaker: For about thirty years now or over thirty years now, we've (02:02):
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Speaker: been studying the luminescent symbiosis between the Hawaiian (02:05):
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Speaker: bobtail squid and the luminous bacterium Vibrio fischeri. (02:10):
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Speaker: And the squid is endemic to the Hawaiian archipelago. (02:15):
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Speaker: They live in shallow sand flats. (02:18):
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Speaker: And so what we've been studying (02:21):
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Speaker: how the animal gets its symbiont (02:23):
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Speaker: every generation. (02:26):
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Speaker: So starting at the very beginning, when they're babies, (02:27):
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Speaker: the female lays a set of eggs and they hatch. (02:30):
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Speaker: After about twenty days, the (02:33):
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Speaker: animal hatches into the (02:35):
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Speaker: seawater. (02:36):
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Speaker: And what they do is they begin to collect their symbiont from (02:36):
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Speaker: the surrounding seawater. (02:41):
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Speaker: Now, how did the symbiont get into the surrounding seawater? (02:42):
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Speaker: The adults have a light organ that is full of Vibrio fischeri, (02:46):
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Speaker: and they use that light made by Vibrio fischeri to counter (02:50):
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Speaker: illuminate against downwelling moonlight and starlight. (02:54):
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Speaker: And what I mean by counter illuminate is that they put out (02:59):
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Speaker: light out of their bottom surface of the same intensity, (03:02):
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Speaker: angular distribution, and color as the downwelling light from (03:07):
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Speaker: the moon and the stars. (03:11):
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Speaker: And what they're doing is they're hanging up in the water (03:12):
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Speaker: column and letting light come out of their ventral surface, (03:15):
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Speaker: matching the moonlight and starlight, so that a predator (03:19):
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Speaker: sitting underneath them on the bottom can't see them. (03:22):
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Speaker: In other words, they don't cast (03:26):
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Speaker: a shadow, so they're night (03:27):
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Speaker: active predators. (03:29):
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Speaker: Every day at dawn, they bury in the sand. (03:30):
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Speaker: And with actually with the light cue of dawn, they let out of (03:33):
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Speaker: their organ about ninety percent of their symbionts. (03:38):
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Speaker: And then during the day, they grow them back up from those (03:42):
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Speaker: left inside up to make the light organ full so that it can do its (03:46):
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Speaker: job at night. (03:50):
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Speaker: The camouflaging job. (03:51):
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Speaker: Well, it turns out that putting their bacteria out into the (03:52):
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Speaker: surrounding seawater provides the inoculum for the babies. (03:56):
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Speaker: So the babies are born without symbionts. (03:59):
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Speaker: And one of our major questions has been, how do they get those (04:03):
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Speaker: symbionts from the water? (04:07):
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Speaker: How do they choose them? (04:08):
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Speaker: There are five mils and a (04:10):
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Speaker: teaspoon of seawater, and in (04:11):
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Speaker: those five mils there are five (04:13):
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Speaker: million bacteria. (04:16):
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Speaker: And of those five million (04:18):
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Speaker: bacteria, there are only about (04:20):
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Speaker: somewhere around five hundred (04:22):
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Speaker: Vibrio fischeri. (04:24):
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Speaker: The baby has to be able to (04:25):
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Speaker: distinguish the symbiont against (04:27):
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Speaker: that huge background of other (04:30):
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Speaker: bacteria. (04:31):
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Speaker: It makes a biochemical (04:32):
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Speaker: environment that favors (04:34):
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Speaker: collection of Vibrio fischeri, (04:36):
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Speaker: and it does so on the surface of (04:38):
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Speaker: the organ that's going to be (04:40):
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Speaker: colonized. (04:42):
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Speaker: Nothing goes into the organ except Vibrio fischeri. (04:43):
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Speaker: Then the bacteria drive some development of the organ. (04:47):
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Speaker: So the organ goes from being the (04:51):
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Speaker: baby organ to being the shape (04:53):
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Speaker: and function of the adult organ, (04:56):
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Speaker: and the bacteria must be (04:58):
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Speaker: present. (04:59):
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Speaker: The symbiotes must be present in (05:00):
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Speaker: order for that development to (05:02):
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Speaker: happen. (05:03):
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Speaker: And then we study how in the world do they maintain this (05:04):
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Speaker: symbiosis their entire life? (05:09):
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Speaker: In other words, how is it that (05:11):
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Speaker: the bacteria don't overgrow the (05:13):
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Speaker: host, nor does the host (05:15):
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Speaker: eliminate the bacterial (05:17):
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Speaker: symbionts with their immune (05:19):
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Speaker: system? (05:20):
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Speaker: And that's done by this profound circadian rhythm. (05:20):
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Speaker: They vent ninety percent, and (05:24):
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Speaker: then they grow them back up and (05:25):
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Speaker: they vent ninety percent and (05:27):
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Speaker: they grow them back up is (05:28):
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Speaker: amazingly complex, very, you (05:30):
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Speaker: know, it's one host and one (05:33):
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Speaker: symbiont. (05:35):
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Speaker: And, you know, when you think about the fact that the human (05:35):
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Speaker: gut has hundreds if not thousands of species associated (05:38):
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Speaker: with it, try to figure out how that selection occurs. (05:43):
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Speaker: It's very difficult. (05:47):
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Speaker: And so to symbiosis in general, (05:49):
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Speaker: as well as to the biomedical (05:51):
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Speaker: community. (05:53):
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Speaker: What we've been able to do is (05:54):
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Speaker: define something and say, look (05:56):
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Speaker: there. (05:57):
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Speaker: So one example that I've already (05:58):
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Speaker: mentioned to you is this daily (06:00):
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Speaker: rhythm. (06:01):
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Speaker: Well, the human gut and the microbes of the human gut are on (06:02):
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Speaker: a profound circadian rhythm. (06:06):
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Speaker: We were the first to show that symbiosis is on a profound (06:07):
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Speaker: circadian rhythm, because the system is so simple. (06:11):
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Speaker: You know who's doing what? (06:14):
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Speaker: Even though you know who's doing (06:15):
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Speaker: what, it's massively (06:17):
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Speaker: complicated. (06:18):
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Speaker: Yeah, yeah. (06:19):
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Speaker: This is two partners in a very direct relationship. (06:19):
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Speaker: We can see the logic in what (06:22):
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Speaker: each partner is gaining from (06:25):
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Speaker: that relationship. (06:26):
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Speaker: But something like our gut microbiome is a whole ecosystem. (06:26):
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Speaker: Current thinking is that our our (06:31):
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Speaker: view of our immune system as (06:34):
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Speaker: this warden, as this sort of (06:35):
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Speaker: combative thing, it's actually (06:37):
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Speaker: an ambassador. (06:39):
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Speaker: That's right. (06:40):
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Speaker: It's actually in relationship. (06:40):
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Speaker: It's it's negotiating this relationship constantly. (06:42):
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Speaker: And I find that far more exciting as an ecologist. (06:45):
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Speaker: Oh, yeah. (06:49):
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Speaker: You know, the immune system, like in humans, they've always (06:49):
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Speaker: thought the immune system is to work against pathogens. (06:53):
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Speaker: But when I speak to physicians, I always say, okay, you guys, (06:56):
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Speaker: how many pathogens have you had in your life? (06:59):
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Speaker: You know? (07:02):
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Speaker: And they'll say, oh, you know, twenty, thirty, whatever. (07:02):
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Speaker: And the fact of the matter is, is every single day of your (07:05):
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Speaker: life, from the minute you pass down the birth canal, you have (07:08):
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Speaker: those microbes associated with you in your intestine, on your (07:11):
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Speaker: skin, and so on and so forth. (07:15):
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Speaker: What is the most parsimonious explanation for what the immune (07:17):
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Speaker: system is doing? (07:20):
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Speaker: Because it's very expensive to (07:21):
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Speaker: maintain and it's working every (07:23):
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Speaker: day and the cells are changing (07:24):
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Speaker: every day. (07:26):
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Speaker: What it is is it's ecological management system. (07:27):
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Speaker: And the pathogens are spies. (07:30):
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Speaker: And so many of our of our illnesses are an imbalance. (07:32):
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Speaker: You know, there are things that are present in us anyway. (07:36):
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Speaker: It's just getting out of control, which is more like (07:38):
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Speaker: ecosystem collapse than. (07:40):
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Speaker: Than what we usually think of as infection. (07:42):
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Speaker: That's exactly right. (07:45):
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Speaker: To dive back into the into the squid, can the bacteria almost (07:48):
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Speaker: pick and choose? (07:52):
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Speaker: Is it does it exist perfectly (07:53):
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Speaker: happily in the natural (07:54):
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Speaker: environment? (07:56):
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Speaker: Does it have other relationships? (07:56):
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Speaker: That's a really good question. (07:58):
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Speaker: Vibrios which are thought to be host associated microbes, they (08:00):
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Speaker: often have this tendency to go out into an environment. (08:05):
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Speaker: They're usually environmentally (08:09):
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Speaker: acquired, and they go out into (08:10):
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Speaker: the environment, into what they (08:12):
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Speaker: call a viable non-culturable (08:13):
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Speaker: state. (08:15):
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Speaker: They just go into sort of suspended animation. (08:16):
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Speaker: In our case, you only find (08:19):
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Speaker: Vibrio fischeri in Hawaii, where (08:21):
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Speaker: there are populations of adults, (08:24):
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Speaker: there's some there are some free (08:26):
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Speaker: living strains of Vibrio (08:27):
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Speaker: fischeri that don't colonize the (08:28):
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Speaker: animal. (08:30):
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Speaker: There are strains of Vibrio fischeri that are in fish light (08:31):
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Speaker: organs that are not as fit. (08:34):
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Speaker: They're not as capable of colonizing a squid light organ (08:38):
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Speaker: as they are fish light organ. (08:41):
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Speaker: In other words, there are strain differences, but the bacteria (08:42):
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Speaker: gain a huge population boom by living in the light organ (08:45):
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Speaker: because the animal feeds them. (08:50):
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Speaker: The thing that's interesting, too, about this symbiosis is (08:52):
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Speaker: that when you talk about the idea of obligate, we have never (08:55):
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Speaker: in thirty plus years ever found a squid in nature that doesn't (08:59):
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Speaker: have the symbiont. (09:04):
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Speaker: It just euprymna. (09:05):
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Speaker: Scolopes always has the symbiont. (09:07):
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Speaker: And so there has to have been tremendous evolutionary (09:10):
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Speaker: selection pressure to make sure that they have it. (09:13):
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Speaker: Now, when you bring them into the lab, they don't need it. (09:16):
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Speaker: You can keep them, what we call (09:19):
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Speaker: aposymbiotic for the same amount (09:21):
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Speaker: of time. (09:23):
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Speaker: You keep them symbiotic and it (09:23):
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Speaker: doesn't seem to impact (09:24):
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Speaker: longevity. (09:26):
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Speaker: There isn't. (09:26):
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Speaker: It's not also producing a vitamin or anything like that (09:27):
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Speaker: they rely on. (09:30):
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Speaker: Yeah, it's not like the gut microbiota which provide (09:31):
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Speaker: nutrients and provide vitamins and stuff like that. (09:33):
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Speaker: What they provide for the host is light, and that's basically (09:36):
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Speaker: what we've what we've shown. (09:39):
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Speaker: So one can say that it is not physiologically obligate, but (09:41):
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Speaker: it's ecologically obligate. (09:46):
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Speaker: We did an interesting set of experiments over the first few (09:48):
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Speaker: days of the symbiosis. (09:51):
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Speaker: You can cure them with antibiotics and then recolonize. (09:53):
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Speaker: But there comes a time at about (09:57):
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Speaker: seven days that there's a switch (09:58):
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Speaker: that's flipped. (10:00):
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Speaker: And if you cure them, you can't get them to recolonize after (10:02):
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Speaker: after they've been colonized for about seven days. (10:06):
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Speaker: Have you sort of delved into (10:08):
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Speaker: this, the mechanics of of this (10:10):
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Speaker: process? (10:11):
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Speaker: What changes in the light organ? (10:12):
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Speaker: There are significant changes in (10:14):
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Speaker: gene expression that occur at (10:16):
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Speaker: that juncture. (10:19):
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Speaker: It seems like most of them have (10:20):
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Speaker: to do with the turning down of (10:22):
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Speaker: certain genes, which is very (10:24):
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Speaker: interesting. (10:26):
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Speaker: They're probably involved with (10:27):
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Speaker: recognition or something like (10:28):
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Speaker: that that all of a sudden are (10:30):
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Speaker: turned down. (10:31):
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Speaker: So that's not a finished story, (10:32):
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Speaker: but it is something we're (10:35):
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Speaker: working on. (10:36):
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Speaker: Do we know much about the (10:37):
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Speaker: mechanism for how these single (10:38):
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Speaker: bacteria are passed into each (10:41):
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Speaker: crypt. (10:43):
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Speaker: Do we know how how the recognition works? (10:43):
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Speaker: And is it is it actually passing (10:45):
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Speaker: within a cell, or is it going (10:47):
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Speaker: into sort of a little vesicle (10:48):
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Speaker: capsule where it's a security (10:49):
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Speaker: guard and Chex Chex who's coming (10:51):
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Speaker: in? (10:53):
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Speaker: They're all extracellular. (10:53):
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Speaker: Of course, they're collected on the outside and they're (10:55):
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Speaker: collected in in a mucus matrix, the bacteria have to have an (10:58):
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Speaker: exopolysaccharide capsule that sticks them together. (11:02):
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Speaker: And so then what they do is they're there's a chemical (11:05):
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Speaker: called it's a cytobios. (11:09):
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Speaker: So it's a it's a molecule that is made from chitin. (11:12):
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Speaker: And chitin is the stuff that makes the shell of a crab hard. (11:16):
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Speaker: That's chitin. (11:21):
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Speaker: But if you put enzymes on it, it breaks it down to cytobios. (11:22):
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Speaker: And what Vibrio fischeri does, that's amazing. (11:26):
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Speaker: It begins to gather, like I said, and it attaches to a set (11:29):
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Speaker: of cilia that are just outside the light organ. (11:33):
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Speaker: And when it attaches to those silly. (11:37):
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Speaker: It causes a change in gene expression, and that change in (11:39):
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Speaker: gene expression causes the animal to export something that (11:42):
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Speaker: breaks down the chitin that's in the mucus into cytobios, which (11:47):
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Speaker: is just a smaller molecule. (11:52):
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Speaker: And the bacteria are attracted to that. (11:54):
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Speaker: It makes a concentration (11:57):
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Speaker: gradient so that the bacteria (11:59):
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Speaker: are caused. (12:01):
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Speaker: It causes them to swim in to the light organ. (12:02):
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Speaker: So it swims in and it goes through a fire of antimicrobials (12:05):
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Speaker: to which when it was outside gathering, they adapt to low (12:10):
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Speaker: levels of those antimicrobials. (12:15):
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Speaker: And that's probably what keeps everybody else from coming in, (12:18):
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Speaker: is that they can't adapt. (12:21):
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Speaker: And then they go in and then they go through this narrow (12:23):
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Speaker: bottleneck and go in. (12:25):
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Speaker: Then what they do is if a single bacterium goes in, of course, (12:27):
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Speaker: they're not luminous when they're at low numbers. (12:30):
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Speaker: So what happens is, is they get in higher and higher and higher (12:33):
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Speaker: and higher density. (12:36):
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Speaker: And once they're at high density, they turn on the light. (12:38):
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Speaker: What's really interesting is you (12:41):
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Speaker: can make a mutation in the (12:43):
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Speaker: bacteria such that they don't (12:45):
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Speaker: make light. (12:47):
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Speaker: And what happens is, if you give the animal those bacteria that (12:48):
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Speaker: will not be making light and you ask them to colonize, they will (12:52):
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Speaker: colonize for one day, they will go in, they'll stream in, just (12:56):
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Speaker: like wild type. (13:00):
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Speaker: Then it's about twenty four hours. (13:01):
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Speaker: The population is down by fifty percent. (13:03):
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Speaker: By the next day, the population is down even more. (13:06):
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Speaker: The point is that if they don't make light, the animal senses (13:09):
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Speaker: that and says, excuse me, you're not doing your job. (13:13):
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Speaker: You're gone. (13:15):
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Speaker: You're a slacker. (13:16):
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Speaker: I'm not going to feed you. (13:16):
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Speaker: Yeah, I'm not going to feed. (13:18):
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Speaker: I'm not going to feed a cheater. (13:19):
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Speaker: Right? (13:20):
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Speaker: Yeah. (13:21):
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Speaker: Oh, this is so complicated, I love it. (13:21):
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Speaker: So this expulsion, purging them (13:24):
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Speaker: every day is energetically that (13:26):
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Speaker: the best way, the best way of (13:28):
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Speaker: doing it. (13:29):
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Speaker: Sort of kicking them out and then growing them up. (13:29):
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Speaker: Or is this actually more about maintaining your optimum strain. (13:32):
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Speaker: Yeah, that's that's a very interesting question. (13:36):
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Speaker: One of the things that we have found, each crypt is independent (13:39):
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Speaker: and there are three on each side of the organ. (13:43):
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Speaker: And so it turns out that if you (13:45):
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Speaker: go out and you collect adults, (13:47):
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Speaker: you will never find more than (13:50):
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Speaker: six strains. (13:52):
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Speaker: Sometimes you'll find one strain is doing all of them. (13:53):
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Speaker: But what that says is that it's (13:55):
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Speaker: very likely that the limit of (13:58):
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Speaker: the number of strains is the (14:00):
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Speaker: same as the limit of the number (14:01):
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Speaker: of crypts. (14:02):
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Speaker: And so the venting certainly keeps them from having to (14:04):
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Speaker: maintain those bacteria. (14:09):
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Speaker: But one of the things that's interesting is they vent them, (14:11):
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Speaker: you know, right. (14:15):
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Speaker: With the dawn like you, it causes them to vent ninety (14:16):
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Speaker: percent of their symbionts into the surrounding seawater, but (14:20):
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Speaker: they almost immediately grow back up by noon while they're (14:22):
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Speaker: sitting in the sand. (14:26):
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Speaker: They have their full complement, but the bacteria then grow up to (14:27):
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Speaker: fill the light organ. (14:30):
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Speaker: And then they go into this very, very, very slow growth, very (14:31):
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Speaker: slow growth, almost zero, so that they do maintain them (14:36):
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Speaker: through the day. (14:39):
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Speaker: And then when they come out at six in the evening or whatever (14:40):
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Speaker: to go out and forage, they have a full complement that's making (14:44):
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Speaker: as much light as as possible. (14:47):
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Speaker: But the interesting thing that (14:50):
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Speaker: ecologists, every time I say (14:52):
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Speaker: that the venting certainly seeds (14:54):
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Speaker: the surrounding seawater for the (14:57):
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Speaker: juveniles, the ecologists get (14:58):
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Speaker: upset. (15:01):
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Speaker: There's something about altruism (15:01):
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Speaker: or something that it doesn't (15:02):
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Speaker: work. (15:04):
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Speaker: It doesn't work with ecological theory. (15:05):
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Speaker: Yeah, it well, I don't know what I don't know what the problem (15:07):
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Speaker: is, but but if you take babies and you, you have them in the (15:10):
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Speaker: lab and you go and you collect water in Hawaii, and you go (15:16):
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Speaker: farther and farther and farther and farther away from water (15:20):
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Speaker: collected, you know, from adult where adult populations would (15:23):
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Speaker: be, you go farther, you get your water farther and farther away (15:26):
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Speaker: from those adult populations. (15:29):
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Speaker: The harder and harder and harder (15:30):
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Speaker: it is to get those babies (15:32):
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Speaker: colonized. (15:34):
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Speaker: You've got this sort of model (15:34):
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Speaker: organism and this really (15:36):
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Speaker: interesting relationship. (15:37):
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Speaker: And then thirty years of study, (15:38):
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Speaker: you've looked at every little (15:40):
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Speaker: sort of parameter of it, the (15:42):
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Speaker: distance from the adult (15:43):
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Speaker: population experiment. (15:44):
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Speaker: Like usually when I, when I give an interview, I'm just like, oh, (15:45):
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Speaker: we should look into that. (15:48):
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Speaker: And oh, we should look into that. (15:49):
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Speaker: But like you've really explored this space. (15:50):
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Speaker: So I like that we've got such a (15:52):
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Speaker: good picture of what's going on (15:54):
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Speaker: here. (15:55):
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Speaker: I'm sure there's still a lot to come. (15:56):
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Speaker: It's really fun. (15:57):
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Speaker: I just had a student that I shared with a guy named Rudy (15:58):
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Speaker: Rosa, who's on the faculty at University of Lisbon. (16:03):
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Speaker: She came over and worked in my (16:05):
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Speaker: lab to ask the question of how (16:06):
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Speaker: an increase in environmental (16:09):
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Speaker: temperature would impact the (16:10):
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Speaker: symbiosis. (16:13):
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Speaker: And so it was really a cool study because it turned out they (16:14):
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Speaker: do their best at twenty five degrees, and then at twenty (16:17):
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Speaker: seven degrees, they're a little bit stressed at thirty degrees. (16:20):
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Speaker: The embryos only make four crypts instead of six crypts. (16:24):
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Speaker: Whoa. (16:29):
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Speaker: And it turns out that the that the Crips developed, the three (16:29):
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Speaker: on each side developed sequentially so that there's a (16:33):
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Speaker: really mature crypt, an intermediately mature crypt, and (16:36):
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Speaker: then one that's just been made in the day before they hatch. (16:40):
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Speaker: And the third crypt, which we found in a previous study, acts (16:44):
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Speaker: as a reservoir in case the more mature crypts, they lose their (16:49):
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Speaker: symbiosis early on. (16:53):
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Speaker: If something happens and they lose their symbiosis, that third (16:55):
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Speaker: crypt will mature and then it doesn't vent like the other two (16:58):
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Speaker: crypts do at the beginning. (17:03):
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Speaker: And what it does is it creates a reservoir and will repopulate (17:05):
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Speaker: the other crypts. (17:09):
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Speaker: It's an appendix. (17:10):
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Speaker: If the embryos are raised at (17:12):
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Speaker: thirty degrees, they don't make (17:15):
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Speaker: crypt three, so they lose their (17:16):
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Speaker: reservoir. (17:17):
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Speaker: Wow. (17:18):
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Speaker: The failsafe device is removed. (17:18):
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undefined

Speaker: They they lose their insurance policy. (17:21):
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Speaker: Oh, this is every little angle we pick into. (17:24):
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Speaker: This just gets more and more interesting. (17:26):
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Speaker: We may lose the symbiosis with (17:28):
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Speaker: climate change because of the (17:30):
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Speaker: fact that the resilience is (17:32):
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Speaker: compromised, the reseeding of (17:34):
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Speaker: the other crypts that's still (17:36):
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Speaker: just in this porous stage at the (17:38):
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Speaker: beginning. (17:40):
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Speaker: Or can they if something happens, if if they lose one (17:41):
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Speaker: crypt through, something goes wrong, can they later receive (17:44):
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Speaker: that in life? (17:47):
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Speaker: Or do you do you sometimes find an adult with one of the bulbs (17:48):
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Speaker: are blown out, you know? (17:51):
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Speaker: You know what, Tom? (17:53):
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Speaker: We have never found an adult that doesn't have a fully (17:54):
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Speaker: functional light organ. (17:57):
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Speaker: And I don't know whether that (17:58):
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Speaker: means that that those that don't (17:59):
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Speaker: have them get picked off by (18:00):
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Speaker: predators. (18:02):
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Speaker: But we've never found an adult that isn't fully functional. (18:02):
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Speaker: There's something fragile about the first seven days that after (18:06):
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Speaker: seven days, they apparently don't become perturbed because (18:10):
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Speaker: if you do perturb them, you can't recolonize them. (18:15):
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Speaker: Are there any cheats? (18:17):
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Speaker: Is it possible for them to get (18:18):
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Speaker: sort of an infection in the (18:20):
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Speaker: light organ? (18:22):
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Speaker: One of the things that's really remarkable Archival is that (18:22):
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Speaker: usually when you have a colony of bacteria like that. (18:26):
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Speaker: That's a playground for a virus, right? (18:30):
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Speaker: Bacteriophage. (18:33):
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Speaker: You know, the light organ stays open. (18:34):
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Speaker: This pathway, this migration path through which it lets the (18:36):
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Speaker: bacteria out into the environment each day. (18:40):
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Speaker: And so that migration path stays open. (18:43):
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Speaker: And so the question is why doesn't a virus sweep. (18:46):
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Speaker: Why does the virus get in there and kill everybody? (18:50):
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Speaker: There was a guy from University of Wisconsin who studied (18:52):
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Speaker: viruses, who came out and did some work on this question. (18:55):
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Speaker: And he tried to find viruses against Vibrio fischeri. (18:59):
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Speaker: And he found one after looking very, very hard. (19:03):
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Speaker: But it only worked against one strain. (19:07):
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Speaker: And he did an experiment, a really cool experiment that if (19:09):
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Speaker: you take that one that's susceptible to this virus and (19:13):
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Speaker: you put it head to head, you co-colonized with the virus and (19:16):
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Speaker: the bacterial strain at the same time they get into the crypt (19:21):
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Speaker: space and they begin to grow and the virus wipes them out. (19:24):
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Speaker: If, on the other hand, if you (19:28):
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Speaker: put the bacteria in first, they (19:29):
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Speaker: go in. (19:32):
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Speaker: They get adapted over a day to the host environment. (19:32):
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Speaker: Then you put the virus in the water, the virus gets in, but it (19:36):
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Speaker: can't do anything. (19:40):
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Speaker: There's something about either a change in the bacteria or the (19:41):
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Speaker: environment that the host creates that doesn't allow (19:45):
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Speaker: phage, while the host is a good shepherd and keeps the wolf out. (19:48):
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undefined

Speaker: The lack of viruses you're seeing in the environment. (19:52):
undefined

Speaker: If this relationship is sort of (19:54):
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Speaker: obligate on both sides, the (19:56):
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Speaker: viruses don't get much chance to (19:58):
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Speaker: to develop. (19:59):
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undefined

Speaker: And apparently I'm you know, I'm (20:02):
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Speaker: not a virologist, but apparently (20:04):
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Speaker: one of the strategies about (20:05):
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Speaker: going into this viable (20:07):
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Speaker: nonculturable state when they go (20:08):
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Speaker: out into the environment is that (20:10):
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Speaker: viruses depend upon bacterial (20:11):
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Speaker: growth. (20:14):
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Speaker: They're just not doing that. (20:14):
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Speaker: The bacteria are just hanging so (20:16):
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Speaker: the viruses can't get a toehold (20:18):
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Speaker: even when they're out in the (20:19):
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Speaker: environment. (20:21):
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Speaker: I can see how this held you for thirty years because it just (20:22):
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Speaker: gets more nuanced. (20:25):
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Speaker: What's so funny, Tom? (20:27):
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Speaker: Oftentimes people will say to (20:28):
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Speaker: me, are you still working on (20:30):
undefined

Speaker: that squid? (20:31):
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Speaker: And it's like, oh my God, every (20:32):
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Speaker: time we open a door, there's (20:33):
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Speaker: something new. (20:35):
undefined

Speaker: And it's amazing. (20:36):
undefined

Speaker: So I mean, one of the things we've been working really hard (20:38):
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Speaker: on recently is one of the things the bacteria do is they get into (20:40):
undefined

Speaker: the crypt, they throw off these vesicles from their surface. (20:44):
undefined

Speaker: Their surface membrane blebs off these vesicles that contain (20:48):
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Speaker: things that are in the space just below the outer membrane. (20:52):
undefined

Speaker: In fact, these are called outer membrane vesicles. (20:56):
undefined

Speaker: And these outer membrane (20:59):
undefined

Speaker: vesicles contain molecules of (21:00):
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Speaker: the bacteria that then get into (21:02):
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Speaker: the host. (21:05):
undefined

Speaker: And there are like two hundred (21:06):
undefined

Speaker: and seventy proteins in these (21:08):
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Speaker: vesicles. (21:10):
undefined

Speaker: And there are a bunch of small RNAs that are very active. (21:12):
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Speaker: These bacterial molecules get into the host cells. (21:16):
undefined

Speaker: Even though the bacteria themselves don't go into the (21:20):
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Speaker: host cells, these molecules of these outer membrane vesicles go (21:22):
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Speaker: into the host cells and they differentially traffic around (21:26):
undefined

Speaker: the host cells. (21:30):
undefined

Speaker: So there's one little small RNA that stays in the cytoplasm. (21:31):
undefined

Speaker: In other words not in the nucleus. (21:37):
undefined

Speaker: It stays in the cytoplasm. (21:39):
undefined

Speaker: And its job, if you can believe (21:41):
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Speaker: this, is to turn down the immune (21:43):
undefined

Speaker: system to calm the immune (21:45):
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Speaker: system. (21:46):
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Speaker: And if you make a mutant such that the outer membrane vesicles (21:47):
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Speaker: do not contain that, the immune system stays roaring and it gets (21:50):
undefined

Speaker: rid of the symbiont. (21:57):
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Speaker: It's their ID card. (21:58):
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undefined

Speaker: Exactly. (22:00):
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Speaker: It says I am the right symbiont. (22:01):
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Speaker: There's another small RNA, goes into the nucleus and binds to (22:04):
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Speaker: euchromatin in the nucleus. (22:11):
undefined

Speaker: And both of them cause big (22:13):
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Speaker: changes in gene expression of (22:15):
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Speaker: the host. (22:17):
undefined

Speaker: So the host. (22:18):
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Speaker: Despite the fact that the (22:19):
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Speaker: bacteria are extracellular, (22:20):
undefined

Speaker: there are molecules from the (22:22):
undefined

Speaker: bacteria that go in and take (22:24):
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Speaker: over certain functions of the (22:26):
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Speaker: host cells. (22:28):
undefined

Speaker: It's pretty wild. (22:29):
undefined

Speaker: It is. (22:30):
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Speaker: We're only able to see it through this relationship. (22:30):
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Speaker: But how many other ways is this kind of animal bacteria (22:33):
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Speaker: relationship going on? (22:36):
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Speaker: Just it's mind blowing. (22:37):
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undefined

Speaker: You know, we evolve with our (22:40):
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Speaker: microbiome and there is a human (22:41):
undefined

Speaker: fingerprint. (22:44):
undefined

Speaker: Each person has their own microbiome, but there is a human (22:45):
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Speaker: set of guilds that are very specific to humans. (22:49):
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Speaker: You can make a tree of the great apes. (22:52):
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Speaker: And they each have their own, their own microbiomes. (22:56):
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Speaker: And that tree of the microbiomes reflects the genetic (22:59):
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Speaker: relationships among them. (23:04):
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Speaker: The one of the interesting things is that I started (23:05):
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Speaker: studying symbiosis when symbiosis was the biggest (23:09):
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Speaker: backwater field going. (23:13):
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Speaker: I mean, there was I mean, (23:15):
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Speaker: because it seemed so rare, you (23:17):
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Speaker: know, it really seemed really (23:19):
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Speaker: rare. (23:21):
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Speaker: And so there were lots of insects have symbioses. (23:21):
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Speaker: Most insects have symbioses. (23:24):
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Speaker: And then there were deep sea hydrothermal vent animals. (23:26):
undefined

Speaker: There were luminous bacteria and particularly fishes and squid. (23:31):
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Speaker: So luminous bacterial symbioses occur in fishes and squid, (23:35):
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Speaker: certain certain species of fishes and squids. (23:39):
undefined

Speaker: So yeah, I mean it's it's really (23:41):
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Speaker: amazing that in two thousand and (23:44):
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Speaker: six, we got next gen sequencing (23:47):
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Speaker: and the cost of sequencing went (23:49):
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Speaker: from six thousand dollars a (23:52):
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Speaker: Megabase to three cents a (23:54):
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Speaker: megabase. (23:56):
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Speaker: And I mean, that was huge. (23:58):
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Speaker: The Human Genome Project, which took three or four years and (24:00):
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Speaker: cost two and a half to three billion dollars to do. (24:05):
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Speaker: Maybe it was billion, I can't remember. (24:09):
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Speaker: You can get your genome (24:10):
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Speaker: sequenced for five hundred (24:11):
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Speaker: dollars. (24:13):
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Speaker: Yeah, in the mail. (24:13):
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undefined

Speaker: I mean, you know, and I'm talking about your genome, not (24:16):
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Speaker: the bacterial genome. (24:18):
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Speaker: That's another story. (24:19):
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Speaker: You can get your microbiome done for one hundred dollars, too. (24:20):
undefined

Speaker: That was incredibly democratizing. (24:23):
undefined

Speaker: And so the community started going out and characterizing the (24:26):
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Speaker: microbiome around the world. (24:29):
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Speaker: And it turns out that it's very common. (24:31):
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Speaker: A shared derived character of (24:34):
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Speaker: all vertebrates is to carry a (24:35):
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Speaker: very complex microbiome that (24:37):
undefined

Speaker: seems to have evolved with each (24:40):
undefined

Speaker: species. (24:42):
undefined

Speaker: Coincidentally, they have an adaptive immune system, the (24:43):
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Speaker: adaptive immune system that has memory and everything is likely (24:46):
undefined

Speaker: principal function, as we were talking about before, is to (24:50):
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Speaker: manage that complex ecosystem. (24:52):
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Speaker: Lots of the invertebrates have simpler symbiotic systems. (24:55):
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Speaker: So, for instance, the guy that (25:01):
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Speaker: we work on, of course, they're (25:02):
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Speaker: going to have microbes in their (25:03):
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Speaker: stomach from the food that they (25:05):
undefined

Speaker: took in. (25:06):
undefined

Speaker: If you feed them and then let them go without food for a (25:07):
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Speaker: couple of days and you take their intestine, there is (25:10):
undefined

Speaker: nothing in there. (25:12):
undefined

Speaker: No microbes. (25:13):
undefined

Speaker: And you look at their skin and (25:15):
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Speaker: you ask, are there other (25:16):
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Speaker: microbes that associate with (25:17):
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Speaker: these animals? (25:19):
undefined

Speaker: Because terrestrial animals have (25:19):
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Speaker: microbes in their skin and (25:21):
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Speaker: vertebrates. (25:22):
undefined

Speaker: Do these guys. (25:23):
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Speaker: You either do um, sem on their skin or you do live dead stain (25:24):
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Speaker: for bacteria on their skin. (25:29):
undefined

Speaker: There are no living bacteria on (25:30):
undefined

Speaker: the skin or on the gills or (25:32):
undefined

Speaker: anything. (25:34):
undefined

Speaker: The males of this species have (25:35):
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Speaker: one symbiont and that's in the (25:36):
undefined

Speaker: light organ. (25:39):
undefined

Speaker: And honeybees are another good example. (25:40):
undefined

Speaker: They have five phylotypes. (25:44):
undefined

Speaker: Every worker honeybee around the world has reproducibly (25:46):
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Speaker: individual to individual, five different kinds of bacteria that (25:51):
undefined

Speaker: are the same every generation and around the world. (25:55):
undefined

Speaker: So they have for my money, they co-evolved. (25:58):
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Speaker: Symbionts of hosts that are invertebrates, like in the (26:02):
undefined

Speaker: marine environments, are usually very simple and oftentimes (26:07):
undefined

Speaker: intracellular vertebrates never have intracellular beneficial, (26:10):
undefined

Speaker: as far as I know, except the mitochondria of course. (26:14):
undefined

Speaker: Do we know much about the origin of bioluminescence? (26:18):
undefined

Speaker: Because there's a little quote I give quite often. (26:21):
undefined

Speaker: I just want to check I'm still up to date on it, that it it (26:23):
undefined

Speaker: originated as a way of detoxifying oxygen, and the fact (26:26):
undefined

Speaker: that it threw out a photon was just an incidental way of (26:29):
undefined

Speaker: getting rid of energy. (26:33):
undefined

Speaker: That's one of the major ideas nobody knows for sure. (26:34):
undefined

Speaker: No one was around making notes. (26:38):
undefined

Speaker: What was the driving? (26:39):
undefined

undefined

Speaker: What was the driving selection? (26:41):
undefined

Speaker: Pressure. (26:42):
undefined

Speaker: But also all luminescent (26:43):
undefined

Speaker: bacteria are facultative (26:45):
undefined

Speaker: anaerobes. (26:48):
undefined

Speaker: What that means is that they can live without oxygen, and they (26:49):
undefined

Speaker: can live with oxygen, right at the interface of anoxic to oxic. (26:52):
undefined

Speaker: I've heard that to more (26:57):
undefined

Speaker: efficiently turn on the genes (26:59):
undefined

Speaker: associated with anaerobic (27:01):
undefined

Speaker: respiration, you want to have (27:02):
undefined

Speaker: something that will suck up the (27:04):
undefined

Speaker: oxygen. (27:05):
undefined

Speaker: And luciferase is something that they've talked about. (27:06):
undefined

Speaker: Once the bacteria are luminous, it's very common for marine (27:09):
undefined

Speaker: fishes and lots of other animals, because vibrios and (27:14):
undefined

Speaker: other luminous bacteria are also great gut symbionts. (27:19):
undefined

Speaker: Almost all luminous bacteria (27:23):
undefined

Speaker: digest chitin, and so if an (27:26):
undefined

Speaker: animal that eats plankton, small (27:28):
undefined

Speaker: shrimps and stuff like that, (27:31):
undefined

Speaker: like a fish that eats small (27:32):
undefined

Speaker: shrimps, will have luminous (27:33):
undefined

Speaker: bacteria in its gut, which is (27:35):
undefined

Speaker: also why we see dead lights on (27:37):
undefined

Speaker: the gut. (27:39):
undefined

Speaker: We see black pigment stopping (27:40):
undefined

Speaker: that reaction from being (27:42):
undefined

Speaker: visible. (27:43):
undefined

Speaker: I think a lot of people think (27:43):
undefined

Speaker: that it's bioluminescent prey, (27:45):
undefined

Speaker: but actually, from what you've (27:47):
undefined

Speaker: just said, I think it's actually (27:49):
undefined

Speaker: the gut microbiome breaking down (27:50):
undefined

Speaker: the prey. (27:51):
undefined

Speaker: That's probably kicking out a bit of light. (27:52):
undefined

Speaker: Yeah, exactly. (27:54):
undefined

Speaker: A lot of us have that wrong. (27:55):
undefined

Speaker: Then a lot of deep sea (27:56):
undefined

Speaker: scientists fixate on, oh, (27:57):
undefined

Speaker: they're eating bioluminescent (27:59):
undefined

Speaker: things, and that's why they're (28:00):
undefined

Speaker: shielding it. (28:01):
undefined

Speaker: But actually, it might just be the digestion. (28:01):
undefined

Speaker: That's interesting, because a lot of you would think that a (28:04):
undefined

Speaker: lot of things that weren't used to being in guts would die if (28:07):
undefined

Speaker: they were eaten, you know? (28:12):
undefined

Speaker: And whereas the bacteria do just (28:13):
undefined

Speaker: fine, you know, they they like (28:15):
undefined

Speaker: guts. (28:17):
undefined

Speaker: One of the things that we're (28:17):
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Speaker: doing in collaboration, the (28:18):
undefined

Speaker: major player in this is a guy (28:21):
undefined

Speaker: named Oleg Simakov at University (28:22):
undefined

Speaker: of Vienna. (28:25):
undefined

Speaker: And Oleg has a grant from the Moore Foundation and Sanger in (28:25):
undefined

Speaker: England to full genome sequence a bunch of sepiolid. (28:30):
undefined

Speaker: And that's the family in which Euprymna lives. (28:36):
undefined

Speaker: And the Sepiolid family of squids has members or species (28:39):
undefined

Speaker: that are luminous and have luminescent bacterial symbioses, (28:45):
undefined

Speaker: and closely related relatives that don't have luminous (28:48):
undefined

Speaker: bacterial symbioses and don't have the organs. (28:52):
undefined

Speaker: And so what they're doing is (28:55):
undefined

Speaker: they're doing full genome (28:56):
undefined

Speaker: sequence to see what signature (28:57):
undefined

Speaker: of having a luminous organ is in (29:00):
undefined

Speaker: an animal. (29:02):
undefined

Speaker: And so it's a really fun project (29:03):
undefined

Speaker: to see how you make an orphan (29:06):
undefined

Speaker: organ. (29:08):
undefined

Speaker: What are the genes that are are (29:08):
undefined

Speaker: brought in to make an orphan (29:10):
undefined

Speaker: organ? (29:11):
undefined

Speaker: One of the things we do know about the light organ, I think (29:11):
undefined

Speaker: it's not too surprising either. (29:14):
undefined

Speaker: All light organs are like a riff on the eye. (29:16):
undefined

Speaker: So the eye is light receiving, right? (29:19):
undefined

Speaker: And the luminescent organs are light emitting. (29:22):
undefined

Speaker: But they have lenses and they (29:26):
undefined

Speaker: have tapetum, you know, like (29:28):
undefined

Speaker: that. (29:30):
undefined

Speaker: What causes eye shine in the back of the eye? (29:31):
undefined

Speaker: They have that to make sure the (29:34):
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Speaker: light goes in the right (29:35):
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Speaker: direction. (29:36):
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Speaker: Uh, crypts of the light organ (29:37):
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Speaker: are embedded in the ink sac of (29:38):
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Speaker: the squid, and the ink sac acts (29:40):
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Speaker: as an iris, and that's more or (29:43):
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Speaker: less light out the same way your (29:44):
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Speaker: eye does. (29:46):
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Speaker: They control the light output in two ways one, by withholding (29:47):
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Speaker: oxygen from the symbionts, and the other is by the diverticula (29:50):
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Speaker: of the ink sac. (29:56):
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Speaker: One's a dimmer switch and one is a screen. (29:57):
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Speaker: Yeah, it's very interesting. (30:00):
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Speaker: So we had a paper in PNAS on the (30:02):
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Speaker: full genome sequence of euprymna (30:05):
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Speaker: scolopes. (30:08):
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Speaker: Five or six years ago. (30:09):
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Speaker: And Belcaid was the was the first author on that one. (30:10):
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Speaker: And and what they showed was (30:15):
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Speaker: that the light organ, the (30:17):
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Speaker: genetics suggests that it's a (30:19):
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Speaker: riff on the I. So it's borrowing (30:21):
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Speaker: a lot because it has very (30:23):
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Speaker: similar. (30:25):
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Speaker: Oh, it's not convergent (30:25):
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Speaker: evolution because this is a good (30:27):
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Speaker: process. (30:28):
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Speaker: This is actually borrowing the genes and the ideas of an eye. (30:29):
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Speaker: Yes. (30:33):
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Speaker: Oh that's cool. (30:33):
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Speaker: Yes. (30:35):
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Speaker: And in fact, in fact, the the (30:35):
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Speaker: genes that drive eye (30:37):
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Speaker: development, there are four of (30:39):
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Speaker: them. (30:41):
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Speaker: The genes that drive eye (30:41):
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Speaker: development are the same genes (30:43):
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Speaker: that drive light organ (30:44):
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Speaker: development. (30:45):
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Speaker: And so it's very close. (30:46):
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Speaker: Now this is super different. (30:48):
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Speaker: So the females of Euprymna and lots of other squids, the (30:50):
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Speaker: females have an organ that is associated with the production (30:54):
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Speaker: of their eggs. (30:59):
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Speaker: This organ in the females. (31:00):
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Speaker: This symbiotic organ, only in mature females is a consortium (31:02):
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Speaker: of like twenty bacteria, different bacterial species. (31:06):
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Speaker: On the surface of every egg. (31:10):
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Speaker: She layers a bunch of bacteria from that organ. (31:12):
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Speaker: Those bacteria keep the eggs from being felled by fungi and (31:15):
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Speaker: killed by fungi. (31:20):
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Speaker: That's a really cool thing. (31:21):
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Speaker: So the females have two symbiotic organs, not just the (31:22):
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Speaker: light organ, but this other one. (31:25):
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Speaker: Oh, and that's pretty common (31:27):
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Speaker: across the across the squids, (31:28):
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Speaker: isn't it? (31:30):
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Speaker: I think the cuttlefish do similar. (31:31):
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Speaker: Cuttlefish have this. (31:33):
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Speaker: It's called the accessory nidamental gland. (31:35):
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Speaker: Cuttlefish have it. (31:37):
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Speaker: The cuttlefish don't have luminous bacteria, but they have (31:38):
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Speaker: accessory nidamental glands. (31:42):
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Speaker: They're still biochemists. (31:44):
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undefined

Speaker: They're still working with this. (31:45):
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Speaker: I started in the fish world. (31:47):
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Speaker: I worked on fish as a graduate student at UCLA. (31:49):
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Speaker: So my study site was the central Philippines. (31:52):
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Speaker: And I worked on a fish called a naked or a slip mouth. (31:54):
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Speaker: And they have a light organ with (31:57):
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Speaker: luminous bacteria that is circum (31:58):
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Speaker: esophageal. (32:00):
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Speaker: And they are also nocturnal and (32:01):
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Speaker: they also use it in (32:02):
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Speaker: illumination. (32:04):
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Speaker: Of course, counter-illumination (32:05):
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Speaker: is like the most common thing in (32:07):
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Speaker: the world in the ocean, (32:09):
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Speaker: especially in the mesopelagic (32:10):
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Speaker: zone. (32:11):
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Speaker: All those bristlemouths and all (32:11):
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Speaker: those everything, everything is (32:14):
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Speaker: like hatchetfishes and all that (32:15):
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Speaker: and the detail that they can (32:17):
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Speaker: tune, that light, the feedback (32:19):
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Speaker: loop between their eyes and the (32:20):
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Speaker: light organ. (32:22):
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Speaker: Oh, it's amazing. (32:23):
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Speaker: And that's all autogenic. (32:24):
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Speaker: You know, most of the (32:26):
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Speaker: mesopelagic stuff is autogenic, (32:27):
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Speaker: except the lures on the the (32:28):
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Speaker: ceratioid anglerfishes. (32:30):
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Speaker: I love that sort of bacteria. (32:33):
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Speaker: Just found a way of detoxifying or increasing the efficiency by (32:34):
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Speaker: removing oxygen, and it just happened to kick out a photon (32:38):
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Speaker: and then accidentally. (32:41):
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Speaker: It is the most common form of communication on planet Earth. (32:43):
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Speaker: You know, they came up with that before their eyes. (32:46):
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undefined

Speaker: Now, one of the things that (32:49):
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Speaker: isn't known is whether or not (32:50):
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Speaker: luminescence evolved. (32:53):
undefined

Speaker: At the same time, vision evolved in animals. (32:55):
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Speaker: That is that's an open question. (32:58):
undefined

Speaker: So luminescence bacterial luminescence in symbiosis is (33:00):
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Speaker: only found with one exception in animals with very good vision. (33:05):
undefined

Speaker: So fishes and squids have luminous bacterial symbiosis. (33:10):
undefined

Speaker: And then there's one intracellular bacterial symbiont (33:14):
undefined

Speaker: in a type of tunicate that doesn't have eyes. (33:18):
undefined

Speaker: Things that have luminous bacterial symbiosis have eyes. (33:22):
undefined

Speaker: The things that are autogenic. (33:25):
undefined

Speaker: Most of the luminescence in the (33:27):
undefined

Speaker: world is autogenic, and that is, (33:29):
undefined

Speaker: you know, there aren't any (33:31):
undefined

Speaker: bacteria involved and the (33:32):
undefined

Speaker: animals make their own (33:33):
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Speaker: chemicals. (33:34):
undefined

Speaker: So all those bristlemouths, almost all of the mesopelagic (33:35):
undefined

Speaker: luminescence is is not bacterial, it's autogenic. (33:40):
undefined

Speaker: They make their own chemicals. (33:44):
undefined

Speaker: How did they get that skill? (33:46):
undefined

Speaker: Woody Hastings was my academic grandfather. (33:47):
undefined

Speaker: He was a big luminescence guy and thought about this a lot. (33:50):
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Speaker: What he would say is that (33:54):
undefined

Speaker: luminescence evolved (33:56):
undefined

Speaker: independently, probably thirty (33:58):
undefined

Speaker: times. (34:00):
undefined

Speaker: Many, many, many of the animals (34:01):
undefined

Speaker: have a luciferin, which is the (34:02):
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Speaker: molecule that gets oxidized by (34:04):
undefined

Speaker: their luciferase. (34:06):
undefined

Speaker: They make this molecule called (34:08):
undefined

Speaker: luciferin, which is the (34:09):
undefined

Speaker: condensation of three different (34:11):
undefined

Speaker: amino acids. (34:13):
undefined

Speaker: Those three different amino acids make the chemistry that, (34:14):
undefined

Speaker: when oxidized, gives off photon. (34:17):
undefined

Speaker: Not too complex not to arise a few times and then be right. (34:20):
undefined

Speaker: Be made use of. (34:24):
undefined

Speaker: And I love the little shout out of luciferin, luciferase and (34:25):
undefined

Speaker: Lucifer, the light bringer. (34:28):
undefined

Speaker: I know. (34:30):
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Speaker: Isn't that amazing? (34:30):
undefined

Speaker: It's very metal. (34:31):
undefined
undefined

Speaker: Mhm. (34:33):
undefined

Speaker: Thank you so much for for having a chat. (34:35):
undefined

Speaker: I thoroughly enjoyed that. (34:37):
undefined

Speaker: I've got a lot of big questions bouncing around in my head now. (34:39):
undefined

undefined
undefined

Speaker: Well if, if you need anything just let me know. (34:43):
undefined

Speaker: I'm excited to introduce you to the Unseen Ocean Collective, a (34:49):
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Speaker: new art and science team made up of four trailblazing women the (34:53):
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Speaker: artists Megan Jones, Nilanjana Das, Kirstin Keller and me. (34:56):
undefined

Speaker: Lara Beckmann, a marine biologist. (35:00):
undefined

Speaker: Together, we co-founded the (35:02):
undefined

Speaker: collective to widen the scope of (35:03):
undefined

Speaker: science communication through (35:05):
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Speaker: fine art, outreach events and (35:06):
undefined

Speaker: international exhibitions. (35:08):
undefined

Speaker: This all started from my idea to (35:10):
undefined

Speaker: bring this incredible deep sea (35:11):
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Speaker: footage that I work with to (35:12):
undefined

Speaker: artists turning science into (35:14):
undefined

Speaker: stories that reach new (35:15):
undefined

Speaker: audiences. (35:17):
undefined

Speaker: At the heart of our work is a (35:17):
undefined

Speaker: mission to reveal the deep (35:19):
undefined

Speaker: oceans, unseen worlds through (35:20):
undefined

Speaker: art and science, inspiring (35:22):
undefined

Speaker: curiosity, dialogue and (35:24):
undefined

Speaker: stewardship for the future of (35:25):
undefined

Speaker: our oceans. (35:26):
undefined

Speaker: We want to take this amazing world out of the science bubble (35:27):
undefined

Speaker: and into the hands and imaginations of everyone, so (35:30):
undefined

Speaker: people who might never open a research paper can still be (35:33):
undefined

Speaker: moved by the oceans hidden life. (35:36):
undefined

Speaker: Right now we are working with ROV footage from NOAA seascape (35:38):
undefined

Speaker: Alaska Expeditions in twenty twenty three, which captured (35:42):
undefined

Speaker: amazingly diverse and dense deep sea coral and sponge communities (35:45):
undefined

Speaker: which are full of life that most people never get to see. (35:48):
undefined

Speaker: We are turning that unseen world (35:51):
undefined

Speaker: and the science behind it into (35:53):
undefined

Speaker: artworks for everyone to (35:54):
undefined

Speaker: experience. (35:55):
undefined

Speaker: Our works range from acrylic on canvas, gouache and watercolor (35:57):
undefined

Speaker: paintings, to 3D models and immersive sculptures to video (36:00):
undefined

Speaker: installations, all created in our own styles but inspired by (36:04):
undefined

Speaker: real, deep sea life. (36:07):
undefined

Speaker: We just kicked off with our (36:09):
undefined

Speaker: first exhibition at the Swedish (36:10):
undefined

Speaker: Biodiversity Symposium last (36:11):
undefined

Speaker: month, and next we will bring (36:13):
undefined

Speaker: our works to Juneau, Alaska in (36:14):
undefined

Speaker: February twenty twenty six to (36:16):
undefined

Speaker: introduce local communities to (36:18):
undefined

Speaker: the magic of these underwater (36:20):
undefined

Speaker: forests right in their own (36:21):
undefined

Speaker: backyard. (36:22):
undefined

Speaker: And then in April twenty twenty six, we will be in Spokane, (36:23):
undefined

Speaker: Washington, for a month long exhibit and outreach program. (36:26):
undefined

Speaker: Spokane doesn't have a zoo, (36:29):
undefined

Speaker: aquarium, or a natural history (36:30):
undefined

Speaker: museum, and it's far away from (36:32):
undefined

Speaker: the ocean. (36:33):
undefined

Speaker: So we are especially excited to (36:34):
undefined

Speaker: bring deep sea education and (36:35):
undefined

Speaker: experiences to an underserved (36:37):
undefined

Speaker: community. (36:38):
undefined

Speaker: Our Spokane program will include public talks, school activities (36:39):
undefined

Speaker: with Steam kids, and even treasure hunts, hidden kids and (36:43):
undefined

Speaker: also adults to learn about the deep ocean, the corals and (36:46):
undefined

Speaker: sponges, their associates, and also their importance. (36:49):
undefined

Speaker: Our work is supported by the (36:52):
undefined

Speaker: British Ecological Society (36:54):
undefined

Speaker: Outreach Grant, Spokane's Art (36:55):
undefined

Speaker: Grant Award, saga and cultural (36:57):
undefined

Speaker: funding. (37:00):
undefined

Speaker: If you want to follow along, you can find us on Instagram and (37:00):
undefined

Speaker: Bluesky at Unseen Collective. (37:03):
undefined

Speaker: Or you can also read more at unseen. (37:05):
undefined

Speaker: Com. (37:08):
undefined

Speaker: And that was a pressurized (37:09):
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Speaker: version of one of our longer (37:10):
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Speaker: podcast episodes. (37:12):
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Speaker: If you enjoyed that and you would like to hear the full (37:14):
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Speaker: length episode, just match the episode numbers and you'll be (37:17):
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Speaker: able to find the full length version in the feed. (37:20):
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Speaker: Thanks for listening. (37:23):
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Speaker: We'll see you next time. (37:24):
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Speaker: And I miss you already. (37:25):
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Speaker: Oh, yeah. (37:31):
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PRESSURISED: 063 – Bioluminescent Symbiosis with Margaret McFall-Ngai

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.css-14f5ked{margin:0;word-break:break-word;display:-webkit-box;-webkit-box-orient:vertical;box-orient:vertical;-webkit-line-clamp:2;overflow:hidden;}PRESSURISED: 063 – Bioluminescent Symbiosis with Margaret McFall-Ngai