At various facets of life, I came across many who looked at me in awe when I tell them that I study Chemistry, because it is considered to be a subject that is difficult to understand easily and complicated to learn. However, many are unaware that there are millions of chemical reactions that occur in and around us every time and nature in itself is a wonderful laboratory, performing marvelous chemical reactions in just the perfect way which makes chemistry fascinating to people like me who always admired its science. For a long time, man has been trying to explore this chemistry in order to understand and learn from it, but is unable to mimic even the simplest of naturally occurring chemical reactions owing to its complexity which is still, a challenge!
Among such reactions, those that involve ‘enzymes’ fascinate me. My research is all about exploiting the science behind it in order to aid in carrying out versatile chemical transformations used by pharmaceutical industries which aim to manufacture life saving drugs economically without harming the environment.
Figure 1. Ligase is an enzyme that catalyses the joining of two big molecules to form new ones
Enzymes are biological catalysts (or biocatalysts) that help speed up a metabolic reaction under normal physiological conditions such as temperature and pressure in living systems. Catalysts are chemical substances that alter the speed of a chemical reaction without being consumed in the reaction. The importance of enzymes in such chemical reactions are such that they occur in a fraction of a second, but would take a trillion years to complete in its absence.
All living organisms produce enzymes which keep life moving. For instance, taking a piece of bread and chewing it slowly will feel tasteless initially, but after sometime, one can feel that it slowly sweetens. What actually happens is the starch in the bread that is tasteless is broken down by amylase (an enzyme in our saliva) into sugars which taste sweet.
In general, enzymes vary from one organism to the other. The enzymes produced by one of the tiniest organisms, the bacteria are versatile and are highly valuable for pharmaceutical industries to catalyse drug synthesis. Some bacteria harvest energy by combining hydrogen and oxygen present in the atmosphere and carry out numerous chemical conversions during their metabolism, using enzymes. Enzymes have proved to be superior catalysts in comparison with man-made catalysts owing to the cost of production, energy consumption, product purity and yield.
Figure 2. Enzymes helping to digest food in the mouth. ‘E’ here stands for enzyme
One of the tedious processes in drug synthesis is their purification which is indispensable because a less purified product can be toxic and sometimes, fatal! This is where enzymes are extremely useful. They assist in preparing very pure target compounds which need little or no purifications to be done before marketing them.
Structurally, enzymes are protein based molecules that encapsulate cheap metals like nickel and iron. These metals act as ‘active sites’ that are responsible for catalytic activity and the protein moiety acts as scaffolding. This is in contrast to man-made catalysts which employ expensive metals like platinum and palladium.
During the past ten years, various books and articles came into existence highlighting the different biocatalysts available along with the details of the type or class of reactions they can accomplish. But what is that, which makes it a challenge for pharmaceuticals to make use of enzymes?
Well, it sounds easy to say ‘using the enzyme’, but there is a lot more to watch out when an enzyme is used. They become highly unstable when exposed to the atmosphere and degrade, thus losing their activity. Inside a living system, enzymes are contained at physiological conditions that give a more hospitable environment thereby, keeping them stable. However, such challenges can be circumvented with improved techniques which industries are currently pursuing.
All enzymes possess non protein parts called coenzymes or cofactors that are constantly recycled or reused during cell metabolism. Sufficient cofactor availability is an essential criteria for the en- zymes to catalyse a reaction. However, these cofactors are highly challenging to synthesise because of their mighty structures that make their fabrication process a complicated and an expensive one. Industries suffer from the lack of efficient cofactor regeneration systems which is the need of the hour.
I am currently developing a solution to this problem by using a charcoal based system for the efficient regeneration of useful cofactors for drug synthesis. And how do I do that? Well, that will take another huge essay to explain and I look forward to writing more if given a chance
Until then……! CHEERS 😉
Notes:
Picture 1 downloaded from https://brainfoodv.tumblr.com/
Picture 2 downloaded from https://blog.longnaturalhealth.com/digestive-enzymes-thera-zyme-pan/