Essential lysine residue in glutathione reductase: chemical modification by pyridoxal 5'-phosphate.

Biochemistry and molecular biology international

PubMedID: 7663438

Pandey A, Katiyar SS. Essential lysine residue in glutathione reductase: chemical modification by pyridoxal 5'-phosphate. Biochem Mol Biol Int. 1995;36(2):347-54.
Yeast glutathione reductase was inactivated by pyridoxal 5'-phosphate. The inhibition was reversed by dilution. The enzyme-pyridoxal 5'-phosphate complex on reduction with sodium borohydride gave a characteristic absorption maximum at 325 nm and fluorescence maximum at 395 nm when exciated at 325 nm. These results were consistent with the reaction of epsilon-amino group of lysine residue of the enzyme with pyridoxal 5'-phosphate. The enzyme was protected against pyridoxal 5'-phosphate inhibition by NADP indicating thereby that the essential lysine residues are present during the NADP binding site.