Page 73 - General Biochemistry

The chemistry of metabolism

There are about 3000 reactions in human cell. All these reactions

are divided into six categories:
1. Oxidation-reduction reactions
2. Group transfer reactions
3. Hydrolysis reactions
4. Nonhydrolytic cleavage reactions
5. Isomerization and rearrangement reactions
6. Bond formation reactions using energy from ATP

1. Oxidation-reduction reactions

Oxidation-reduction reactions are those in which electrons are transferred from one
molecule or atom to another

Enzymes: oxidoreductases

- oxidases -peroxidases

-dehydrogenases -oxigenases

- Coenzymes: NAD+, NADP+, FAD+, FMN+

- Example:

2. Group transfer reactions

Transfer of a chemical functional group from one molecule to another
(intermolecular) or group transfer within a single molecule (intramolecular)

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