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They are enzymes which are composed of simple proteins.
Example: Amylase enzyme.
(For reading only) amylase is an enzyme secreted by salivary glands, which changes starch into sugar.
Complex enzymes
They are enzymes which consist of:-
1- Protein part
2- Non protein part: This part may be an atom of metal (iron, copper, magnesium) or an organic molecular called coenzyme, non protein part is the active site of enzyme molecule.
Example: Catalase enzyme
(For reading only) catalase enzymes speeds up the decomposition of hydrogen peroxide H2O2 into water and oxygen
The active site of enzyme
Every enzyme has one or more active sites
Active site: A stereoisomer which is responsible for enzyme work
1- The active site of an enzyme (E) links with the substrate (S) forming enzyme-substrate complex (ES).
2- The complex decomposes, products of reaction are formed and the enzyme gets released.
Fig. (12) The mechanism of enzyme
Temperature
Every enzyme has a different optimum temperature (the temperature on which the enzyme becomes most active).
à When the temp. of an enzyme increases more than its optimum temperature, its activity decreases gradually until it stops due to the change of its structure.
à When the temp. of an enzyme becomes less than its optimum temperature, its activity also decreases gradually. Enzyme activity stops at 0◦C (but it become active again when its temperature increases).
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