Reaction: 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate + H2O + NAD+ = 3-dehydroquinate + NH3 + NADP+ + H+
For diagram of reaction click here.
Glossary: 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate = 2-amino-2,3,7-trideoxy-D-lyxo-hept-6-ulosonate
Other name(s): DHQ synthase II; MJ1249 (gene name); aroB' (gene name)
Systematic name: 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate:NAD+ oxidoreductase (deaminating)
Comments: The enzyme, which was isolated from the archaeon Methanocaldococcus jannaschii, plays a key role in an alternative pathway for the biosynthesis of 3-dehydroquinate (DHQ), an intermediate of the canonical pathway for the biosynthesis of aromatic amino acids. The enzyme catalyses a two-step reaction - an oxidative deamination, followed by cyclization.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
1. White, R.H. L-Aspartate semialdehyde and a 6-deoxy-5-ketohexose 1-phosphate are the precursors to the aromatic amino acids in Methanocaldococcus jannaschii. Biochemistry 43 (2004) 7618-7627. [PMID: 15182204]