Pretty much all the enzymes are proteins, except ribozymes that act as biocatalysts and artificial enzymes which are developed by synthetic organic chemists to imitate enzymes.

Enzymes are present in all the living cells and carry out the essential functions of the living organisms. All enzymes are proteins, with couple of exceptions mentioned above. However, not all proteins are enzymes: for example, casein, soy protein, gelatin, etc., are broken down to smaller peptides and amino acids before they are consumed. Enzymes, by their mere presence, and without being consumed, speed up the hydrolysis of proteins.

In other words, enzymes are biocatalysts that can be used over and over. Like any other protein, enzymes are made up of long chains of amino acids that are held together by peptide bonds. There are several enzymes, such as those commonly found in digestive tract: Pepsin and Trypsin that break down proteins to peptides and amino acids, lipases that break down fats into fatty acids and glycerol, and amylases that break down starch to simple sugars. Unlike inorganic catalysts, enzymes are highly specific and pharmaceutical and biotechnology companies exploit this unique feature to potentially make drugs and drug intermediates.

Most of the enzymes are manufactured by submerged and solid-state fermentation process; some are extracted from plants and animal glands. Enzymes are used in a wide variety of industrial applications ranging from animal feeds, meat, leather, food, bio ethanol, biotechnology, biomedical, and many more industrial segments. One of the earlier uses of enzymes was the manufacture of cheese using the stomach extracts of young calves. Today this is significantly replaced by the enzyme chymosin, produced by recombinant cultures.

Over the years research work on enzymes led to several Nobel prizes and revolutionized recombinant technology. More than 30 years ago, the introduction of recombinant DNA technology as a tool for the biological sciences transformed the study of life. Some of the enzymes that revolutionized this field are Restriction enzymes, DNA Ligases, and Polymerase Chain Reactions (PCR), which enabled the production of large quantities of a specific DNA from a complex DNA template in a simple enzymatic reaction. Without these enzymes we would not have seen such rapid progress in biotechnology.

In biotechnology and many other scientific fields there is enormous amount of potential for the discovery of new enzymes and applications of existing enzymes to improve the quality of food and feed.

The following link is the text from Nobel Prize winning speech on enzymes, must read for people who are interested in enzymes: nobelprize.org/nobel_prizes/chemistry/laureates/1972/presentation-speech.html 

Comments (1)
Vijai Pasupuleti,   December 3rd, 2007