title: Essential lysine residue in glutathione reductase: chemical modification by pyridoxal 5'-phosphate.
abstract: 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.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Kanpur.
authors.forename: A
authors.initials: A
authors.lastname: Pandey
authors.forename: S S
authors.initials: SS
authors.lastname: Katiyar
mesh_terms: D000249:Adenosine Monophosphate / Q000494:pharmacology; D001665:Binding Sites; D001894:Borohydrides / Q000378:metabolism; D005978:Glutathione / Q000494:pharmacology; D005980:Glutathione Reductase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism*; D009243:NAD / Q000494:pharmacology; D009249:NADP / Q000378:metabolism / Q000494:pharmacology; D011732:Pyridoxal Phosphate / Q000378:metabolism / Q000494:pharmacology*; D012545:Schiff Bases / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D015003:Yeasts / Q000201:enzymology
chemical_list: D001894:Borohydrides; D012545:Schiff Bases; D009243:NAD; D000249:Adenosine Monophosphate; D009249:NADP; D011732:Pyridoxal Phosphate; C025364:sodium borohydride; D005980:Glutathione Reductase; D005978:Glutathione; D008239:Lysine