Reaction: (S)-2-amino-6-oxohexanoate + NADP+ + AMP + diphosphate = L-2-aminoadipate + NADPH + H+ + ATP (overall reaction)
(1a) L-2-aminoadipyl-[LYS2 peptidyl-carrier-protein] + AMP + diphosphate = L-2-aminoadipate + holo-[LYS2 peptidyl-carrier-protein] + ATP
(1b) (S)-2-amino-6-oxohexanoate + holo-[LYS2 peptidyl-carrier-protein] + NADP+ = L-2-aminoadipyl-[LYS2 peptidyl-carrier-protein] + NADPH + H+
Glossary: L-2-aminoadipate = (2S)-2-aminohexanedioate
Other name(s): LYS2; α-aminoadipate reductase
Systematic name: (S)-2-amino-6-oxohexanoate:NADP+ oxidoreductase (ATP-forming)
Comments: This enzyme, characterized from the yeast Saccharomyces cerevisiae, catalyses the reduction of L-2-aminoadipate to (S)-2-amino-6-oxohexanoate during L-lysine biosynthesis. An adenylation domain activates the substrate at the expense of ATP hydrolysis, and forms L-2-aminoadipate adenylate, which is attached to a peptidyl-carrier protein (PCP) domain. Binding of NADPH results in reductive cleavage of the acyl-S-enzyme intermediate, releasing (S)-2-amino-6-oxohexanoate. Different from EC 1.2.1.31, L-aminoadipate-semialdehyde dehydrogenase, which catalyses a similar transformation in the opposite direction without ATP hydrolysis.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Ehmann, D.E., Gehring, A.M. and Walsh, C.T. Lysine biosynthesis in Saccharomyces cerevisiae: mechanism of α-aminoadipate reductase (Lys2) involves posttranslational phosphopantetheinylation by Lys5. Biochemistry 38 (1999) 6171-6177. [PMID: 10320345]