in Enzymes by

1 Answer

0 votes

In 1961, the International Union of Biochemistry (IUB) appointed an Enzyme Commission which classified enzymes into six different groups/classes. Each class represents the general reaction brought about by the enzymes of that class.

Enzymes are classified into six classes:

Enzyme Class

Reaction catalyzed

Equation

Examples

Oxidoreductases

Oxidation-Reduction

XH2 + Y ―→

X + YH2

Alcohol dehydrogenase, Cytochrome oxidase

Transferase

Group Transfer

C—X + D―→

C + D —X

Transaminase, Transpeptidase, Hexokinase

Hydrolase

Hydrolysis

X—Y + H2O―→

XH + YOH

Protease, Lipase, Amylase, Esterase, Pepsin

Lyases

Addition-Elimination

A—B + X—Y―→

AX + BY

Aminase, Aldolase, Fumarase, Carboxylase

Isomerase

Inter-conversion of isomers

B―→B’

Racemase, Phosphohexose isomerase

Ligases

Condensation (usually ATP dependent)

X + Y―→

X—Y

(ATP ―→ ADP + iP)

Succinate thiokinase, Tryptophan synthetase

 

by