Unlocking the Power of Protease Inhibitors: A Path to Food Security

Today's discussion centers on protease enzyme inhibitors and their potential role in addressing food insecurity by enhancing crop yields. Sharon C dives into what these inhibitors are, how they function, and the significant impact they could have on agriculture, especially in regions struggling with food shortages. Sharon C stumbled upon this topic while researching for another project, and it sparked her interest because it ties together concepts from her AP Biology and AP Environmental Science classes, as well as her passion for plants. Listen in to explore the mechanics of enzymes and how inhibiting specific ones can protect crops from harmful pathogens, ultimately supporting a more sustainable food supply. Join Sharon C and special guest Ada G as they unpack the science behind this fascinating subject and its implications for our ecosystem and future food security.

Episode Transcript

(00:00):
Foreign.
Welcome to Science with Sharon.
I'm your host Sharon Chang, ajunior at Detroit Country Day School.
Today we are tackling thetopic of protease enzyme inhibitors.
What they are, how they work,and how they could possibly help
the human population increasecrop yield to solve the problem of
food insecurity.

(00:20):
I came across this topic whenI was researching for another science
research project earlier thisyear and I thought it was very interesting.
I liked how it combinedinformation that I learned from my
two science classes this year,AP Biology and AP Environmental Science.
I also have a love for plantsand flowers.
I enjoy gardening and am partof the Botany Club at school.
This topic is most closelyrelated to the Cell Energetics unit

(00:43):
in AP Biology as it talks alittle bit about the functions and
behavior of enzymes.
However, the topic also hassome connections with ecology and
the role of photosynthesizersin the ecosystem.
Them Sit back, relax andprepare to get your mind blown.
Poverty is the biggest threatto environmental sustainability.
Because impoverished andunderdeveloped countries focus primarily

(01:05):
on survival due toinsufficient resources, they are
unable to choose sustainable practices.
An estimated 2.33 billionpeople suffer from moderate to extreme
food insecurity, that is 1 in11 people worldwide.
As a result, farmers andscientists are working hard to increase
crop yield and and distributehealthy nutrition across the continent
in order to relieve some ofthe struggles that the impoverished

(01:27):
population deals with.
Recently, there are more andmore microbial pathogens that are
resistant to already available antibiotics.
This risks the bacteriainfiltrating the crops and causing
death or wilted and stuntedgrowth that could limit the yield
of crops that are necessary tofeed the 8 billion people worldwide.
However, there is a strategy.

(01:50):
Protease enzyme inhibitors arenaturally occurring proteins that
help in the defense against pathogens.
Protease enzyme inhibitorshelp to inhibit the growth of bacterial
and fungal pathogens.
First, let's tackle what anenzyme is.
Enzymes are proteins that havespecific active sites based on the
arrangement of the bonds oftheir amino acids.

(02:10):
Molecules bind to the specificactive site and initiate a response.
Bacterial proteases help tospread the pathogen by modifying
the expression of virulentfactors and promoting cell division.
By inhibiting these enzymes,we could help to stop the growth
of magligant pathogens in plants.
This phenomenon was firstobserved with tomatoes infected with

(02:32):
Phytophora infestans that hadincreased levels of trypsin, which
were found to be correlatedwith plants resistant to pathogens.
These inhibitors are examplesof competitive inhibitors, which
means that they mimic thenormal ligand and bind to the active
sites of protease enzymes.
This makes the enzyme inactiveand also blocks normal ligands from

(02:53):
binding with the enzyme.
Now let's focus a little bitmore on trypsin protease inhibitors.
Specifically, there are fourmain natural sources of these trypsin
molecules bovine pancreas,amonvucoid, soybean and lima bean.
Protease inhibitors such astrypsin can work in different ways
depending on their natural source.

(03:14):
For example, seeks of legumessuch as soybeans and lima beans act
as feeding deterrents forinsects by disrupting processes in
their gut.
Instead of reducing pathogens,these molecules help limit the actions
of predators, which could alsohelp benefit the yield of crops overall.
This is just one example ofthe multitude of ways that tribesin
protease inhibitors can help plants.

(03:36):
In order to increase bacterialresistance and have beneficial effects,
scientists could increaseexpression of protease inhibitors.
With this, more harmfulenzymes could be inhibited and more
crops can be produced to helpsolve food insecurity.
However, scientists have to becareful with this phenomenon because
there could also be functionsof protease enzymes that are necessary

(03:57):
for the plant's survival andexcessive inhibition could cause
other problems.
Not only is protecting plantsimportant to human crop yield, it
also helps to sustain thepopulations of higher trophic levels.
Only 10% of available energyis transferred to the next trophic
level.
For example, if plants have atotal of 1000 kilojoules of energy,

(04:18):
primary consumers have a totalof 100 kilojoules of energy.
All organisms in the ecosystemrely on the bottom level of photosynthesizers.
For this reason, having anadequate amount of crops and plants
are crucial to maintainingenough energy flow in our ecosystem.
Also, if there is a deficiencyof crops, primary consumers would
starve and die off.
This would make secondaryconsumers die off and continue to

(04:41):
issue a trophic cascade thatcould impact the entire ecosystem
stability.
Today I'm joined by myclassmate and dear friend, Ada Gong.
Ada, thank you so much forjoining us.
I have a couple of questionsto ask you about this topic and what
you feel the limits of thisphenomena are.
So my first question is whatare the functions of enzymes and

(05:01):
why do you think they playsuch a large role in life?
Enzymes are proteins that havedifferent functions based on their
structures.
Enzymes are in charge of allthe major metabolic processes in
an ecosystem.
For example, the processes ofphotosynthesis are controlled by
enzymes like Rubisco and Pep carboxylase.
Since there's so manydifferent amino acids and so many

(05:22):
different ways to arrangethem, there are a lot of different
functions of enzymes.
Yeah, I really like that.
And my next question is,through your experiences in AP Biology
and AP Environmental Science,what role do you think photosynthesizers
play in our ecosystem?
Yeah, photosynthesizers arereally important because they're
the basis of our food chain,which means they play a big role

(05:43):
in energy flow anddistribution within our ecosystem.
Without photosynthesizers, weare missing primary producers.
This means that primaryconsumers, secondary consumers, and
everything that follows themwould not be able to get enough energy,
which is why photosynthesizersare so crucial in our ecosystem.
Today we talked about proteaseinhibition and how science could

(06:06):
help humanity.
We looked at trypsin proteaseinhibitors that could protect crop
yield to solve some problemsof food insecurity.
Thank you again for listening,and I hope you learned something
new today.