8-amino-7-oxononanoate synthase; part of the cluster involved in the biosynthesis of biotin (also known as vitamin B8 or vitamin H), a water-soluble vitamin that functions as a prosthetic group of many carboxylases, such as acetyl-CoA carboxylase and pyruvate carboxylase (PubMed:20713166). Catalyzes the decarboxylative condensation of pimeloyl-[acyl-carrier protein] and L-alanine to produce 8-amino-7-oxononanoate (AON) (By similarity). 6-carboxyhexanoyl-[ACP] + H(+) + L-alanine = (8S)-8-amino-7-oxononanoate + CO2 + holo-[ACP] Cofactor biosynthesis; biotin biosynthesis. Homodimer. Expression is increased when transferring biotin auxotrophic mutant mycelia from biotin-supplemented medium to biotin-deficient medium. Belongs to the class-II pyridoxal-phosphate-dependent aminotransferase family. BioF subfamily.