Question
What are enzymes?
✓
Answer
Enzymes are biological catalysts. Each biological system requires a different enzyme. So, as compared to conventional catalysts, enzymes are specific and efficient in their action. They are required in only small quantity and work at optimum temperature (310 K) and pH (7.4) under 1 atmospheric pressure. Chemically, they are globular proteins. However, some enzymes are also associated with some non-protein components called the co-factors for their activity. Co-factors are of two types :
(a) Inorganic ions : Such as $Zn ^{2+}, Mg ^{2+}$, $Mn ^{2+}, Fe ^{2+}, Cu ^{2+}, Co ^{2+}$, etc.
(b) Organic molecules : These are of two types :
(i) Co-enzymes : These are usually derived from vitamins such as thymine, riboflavin, niacin, etc. They are loosely held to the protein and can be easily separated by dialysis.
(ii) Prosthetic group : They are also derived from vitamins such as bictin but are tightly held to the protein molecule by covalent bonds. They can be separated only by careful hydrolysis.
(a) Inorganic ions : Such as $Zn ^{2+}, Mg ^{2+}$, $Mn ^{2+}, Fe ^{2+}, Cu ^{2+}, Co ^{2+}$, etc.
(b) Organic molecules : These are of two types :
(i) Co-enzymes : These are usually derived from vitamins such as thymine, riboflavin, niacin, etc. They are loosely held to the protein and can be easily separated by dialysis.
(ii) Prosthetic group : They are also derived from vitamins such as bictin but are tightly held to the protein molecule by covalent bonds. They can be separated only by careful hydrolysis.
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