or immobilised form. [2] of microorganisms as a source material for enzyme production has developed for several important reasons:
(1) There is normally a high specific activity per unit dry weight of product.
(2) Seasonal fluctuations of raw materials and possible shortages due to climatic change or political upheavals do not occur.
(3) In microbes, a wide spectrum of enzyme characteristics, such as pH range and high temperature resistance, is available for selection.
(4) Industrial genetics has greatly increased the possibilities for optimizing enzyme yield and type through strain selection, mutation, induction and selection of growth conditions and, more recently, by using the innovative powers of gene transfer technology and protein engineering.produced enzymes will undoubtedly contribute to the solution of some of the most vital problems with which modern society is confronted, ei food production, energy shortage and preservation, and improvement of the environment, together with numerous medical applications. [3]
1.1.2 Classification of enzymes
Enzymes are divided into six main classes according to the type of reaction catalyzed. They are assigned code numbers which contain four elements separated by points and have the following meaning:
. the number first indicates to which of the six classes the enzyme belongs,
. the second indicates the subclass,
. the third number indicates the sub-subclass, and
. the fourth is the serial number of the enzyme in its sub-subclass.six classes are distinguished in the following manner:
. Oxidoreductasesclass encompasses all enzymes that catalyze redox reactions. The recommended name is dehydrogenase whenever possible, but reductase can also be used. Oxidase is used only when O 2 is the acceptor for reduction. The systematic name is formed according to donor: acceptor oxidoreductase.
. Transferasescatalyze the transfer of a specific group, such as methyl, acyl, amino, glycosyl, or phosphate, from one substance to another. The recommended name is normally acceptor group transferase or donor group transferase. The systematic name is formed according to donor: acceptor group transferase.catalyze the hydrolytic cleavage of CO, CN, CC, and some other bonds. The recommended name often consists simply of the substrate name with the suffix-ase. The systematic name always includes hydrolase. p align="justify">. Lyasescatalyze the cleavage of CC, CO, CN, and other bonds by elimination. The recommended name is, for example, decarboxylase, aldolase, dehydratase (elimination of CO 2 , ...
