Glycogen phosphorylase coenzyme associated is?

ANSWER: (D) Pyridoxal phosphateREF: Lehninger Principles of Biochemistry 4th edition page 562Pyridoxal phosphate is an essential cofactor in the glycogen phosphorylase reaction; itsphosphate group acts as a general acid catalyst, promoting attack by Pi on the glycosidic bond. (This is an unusual role for this cofactor; its more typical role is as a cofactor in amino acid metabolism)Flavin mononucleotide (FMN), or riboflavin-5'-phosphate, is a biomolecule produced from riboflavin (vitamin B2) by the enzyme riboflavin kinase and functions as prosthetic group of various oxidoreductases including NADH dehydrogenase as well as cofactor in biological blue- light photo receptors