The Relevance Of Catalysis In The Human Body
The science behind biocatalytic reactions in our body, and why enzymes are so important for them.
Catalysis, according to the Encyclopedia Britannica, is
in chemistry, the modification of the rate of a chemical reaction, usually an acceleration, by addition of a substance not consumed during the reaction.
In real life, we see leadership seminars trumpeting slogans such as “be a catalyst for change!” We know of cars having catalytic converters to reduce their emissions of pollutive substances.
We’ve heard of the words “catalysis” or “catalysts” so many times over, but we don’t figure out how that applies to our bodies.
Our bodies comprise so many different cells that produce various types of enzymes for different purposes. These enzymes are biological catalysts, or what we shorten to biocatalysts today.
What these enzymes do is that they accelerate the rate of a chemical reaction within the body, and there exist different types of enzymes to carry out various specific biochemical conversions within our body.
Every catalyst has an activity. That activity refers to the rate of the reaction that it is catalysing. In quantifiable terms, how much product can an enzyme be able to produce out of the thing that it is supposed to be converting?
This activity comes about from a feed substrate that can fit into specific compartments of the enzyme, similar to a lock and key mechanism. The enzyme is able to break down specific chemical bonds for the chemical reaction to occur.
The tricky issue with the consumption of drugs is that some of these drugs may be able to fit into the compartments of the many different types of enzymes present in our body and therefore signal odd reactions to occur - this is what we have come to know and describe as the side effect of a drug.
When the activities of certain enzymes decrease, either because of a reduction in the catalyst production rate or a deactivation of certain enzymes, then we’d start to feel symptoms of things not going right within our body.
In our digestive systems, for instance, pepsin enzymes are present to decompose proteins. However, pepsin is only activated under highly acidic conditions, hence carbonic anhydrase (CA) enzymes are required to convert bicarbonate into hydrochloric acid. These enzymes don’t get readily destroyed - hence they qualify to be considered as biocatalysts.
But we can see that intricacy beginning to form in the digestive system. Pepsin is produced by the chief cell, and CA is produced by the parietal cell:
Pepsin is a stomach enzyme that serves to digest proteins found in ingested food.
Gastric chief cells secrete pepsin as an inactive zymogen called pepsinogen.
Parietal cells within the stomach lining secrete hydrochloric acid that lowers the pH of the stomach.
A low pH (1.5 to 2) activates pepsin.
Acetylcholine, gastrin, and histamine stimulate the proton pump in parietal cells to release hydrogen ions and decrease pH.
And we have multiple factors that affect how the cell functions.
As a result, we can see that a person who has a digestive issue may present the symptoms of the digestive issue based on multiple probable sources. If we look at one who cannot digest meat properly, they would have problems with the activity of their pepsin enzymes, which could be a probable result of EITHER:
Their chief cells aren’t producing sufficient pepsin.
The proton pump in the parietal cells isn’t working properly.
The carbonic anhydrase enzymes aren’t producing sufficient hydrochloric acid.
The hydrochloric acid isn’t activating sufficient pepsin to digest the consumed meat.
And if we aren’t able to pinpoint the issue, we could be forced to play guesstimates to find some relief.
For example, betaine hydrochloride could be used to increase the acidity within the stomach.
Or one might go for pepsin supplements or digestive enzyme supplements to support meat digestion within the body.
But if the problem were to be an underproduction of pepsin, we’d come to realise that purchases of betaine hydrochloride would be useless in addressing our concern.
And if it were an issue with carbonic anhydrase activity, we’d be able to see problems appearing with our kidneys and urine too - because carbonic anhydrase regulates the acidity of our blood by determining how much bicarbonate gets eliminated in our urine via the kidneys.
The biochemical complexity just within the digestive system alone is already a mouthful to comprehend. And that’s just only for proteins - we have other types of digestive enzymes that are used to break down carbohydrates and fats in our stomach too.
But what we do need to understand is that all these enzymes are biocatalysts. They’re biological - they’re produced by live microorganisms that reside within our body, and trying to control them for optimal performance isn’t going to be as clear cut or simple as it ought to be. Tinkering with the consumption of individual biochemicals may miss the target completely.
Getting them to function at an optimal level requires a good composition of various nutrients in our diet as well as other aspects of our lifestyle, and it’s never just a clear cut thing of taking supplement A or supplement B - we want to cover our bases adequately.
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