8-amino-7-oxononanoate synthase, Archaea/Proteobacteria type (IPR004723)

Short name: AONS_Archaea/Proteobacteria

Overlapping homologous superfamilies

Family relationships


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]: 6-carboxyhexanoyl-CoA + L-alanine = 8-amino-7-oxononanoate + CoA + CO2

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).

GO terms

Biological Process

GO:0009102 biotin biosynthetic process

Molecular Function

GO:0008710 8-amino-7-oxononanoate synthase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.