8-amino-7-oxononanoate synthase, Archaea/Proteobacteria type (IPR004723)
Short name: AONS_Archaea/Proteobacteria
Overlapping homologous superfamilies
- Pyridoxal phosphate-dependent transferase, major domain (IPR015421)
- Pyridoxal phosphate-dependent transferase (IPR015424)
- 8-amino-7-oxononanoate synthase, Archaea/Proteobacteria type (IPR004723)
- 8-amino-7-oxononanoate synthase, Proteobacteria (IPR022834)
8-amino-7-oxononanoate synthase (AONS) is a pyridoxal 5'-phosphate-dependent enzyme, which catalyses the decarboxylative condensation of L-alanine with pimeloyl-CoA to form 8(S)-amino-7-oxononanoate. This is the first committed step in biotin biosynthesis [PMID: 10642176]:
The enzyme is a symmetrical homodimer with a tertiary structure and active site organisation similar to, but distinct from, those of other PLP-dependent enzymes with known structures. AONS is a critical PLP-binding lysine at the end of a deep cleft that allows access to the pantothenate arm of pimeloyl-CoA. There is a cluster of positively charged residues at the entrance to this cleft, which forms a putative diphosphate binding site for CoA [PMID: 9813126]. Trifluoroalanine irreversibly inhibits this enzyme [PMID: 16557306].
This entry represents 8-amino-7-oxononanoate synthases mainly from Proteobacteria and Archaea. Some members are from Firmicutes and are also covered in (IPR010962).
- TIGR00858 (bioF)