Page 179 - PG 101-Course notes مذكرة النظري 24-25 with spec

Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD

Chemical nature of enzymes

• All enzymes are formed mainly of proteins.

• Some enzymes are formed only of protein part e.g., Proteases and Amylases.

• In other enzymes, the main protein part is attached to a non-protein moiety called

(Prosthetic group).

1-Prosthetic group:

It’s a part of the enzyme structure and can’t be separated from it even by dialysis.

It may be:

● Simple inorganic metal e.g., copper (as in certain oxidizing enzymes).

● or inorganic metal in organic combination e.g., iron-porphyrine in cytochromes

(involved in respiration process).

● or vitamins of the B-complex group e.g. Decarboxylases contain vit. B-6

2-Enzyme activators:

● Some enzymes need for their action the presence of other accompanying substances

which are not parts of the enzymes but assist their actions. Such substances are:

1- Co-factor

2- Co-enzymes

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