Enzyme

Name:
Enzyme
Detailed information:
Any of a unique class of proteins that catalyze a broad spectrum of biochemical reactions. Enzymes are formed in living cells; they are comprised one or more polypeptide chains with molecular weight from 10,000 to a million or more. An important characteristic of enzymes is their specificity, i.e., a given enzyme can catalyze one particular reaction and no others. Six types are recognized, which catalyze the following reactions: (1) redox (oxidoreductases), (2) transfer of specific radicals or groups (transferases), (3) hydrolysis (proteolytic), (4) removal from or addition to the substrate of specific chemical groups (lyases), (5) isomerizaton (isomerases), (6) combination or binding together of substrate units (ligases). The names of enzymes invariably terminate in either -ase or -in. The following partial list indicates some of the more important functions performed by enzymes; among these are the ability to cleave the peptide bonds of proteins (hydrolysis) with simultaneous formation of water; and to decompose sugars and starches to ethyl alcohol and carbon dioxide (fermentation). Enzymes are essential to many biochemical processes, especially in the food, beverage, and pharmaceutical industries.
amylase	starch hydrolysis
carboxylase	decomposes pyruvic acid
cellulase	converts cellulose to glucose
cholinesterase	inactivates acetylcholine
chymotrypsin	hydrolysis of proteins
invertase	converts sucrose to glucose and fructose
lipase	hydrolysis of fats
maltase	converts maltose to glucose
pepsin	hydrolysis of proteins
protease	hydrolysis of peptide linkages
rennin	hydrolysis of proteins
ribonuclease	decomposes RNA
trypsin	splits proteins to amino acids
urease	decomposes urea to NH4 and CO2.
zymase	converts sugars to alcohol and CO2 (fermentation)
Recent research in biomimetic chemistry has succeeded in creating synthetic enzymes that imitate the behavior of natural enzymes, e.g., chymotrypsin, and are almost as effective. See Catalyst; Biomimetic Chemistry; Fermentation; Hydrolysis.