Reaction: 2-amino-4,5-dihydroxy-6-oxo-7-(phosphooxy)heptanoate = 3-amino-4-hydroxybenzoate + phosphate + 2 H2O
For diagram of reaction click here.
Other name(s): 3,4-AHBA synthase; griH (gene name)
Systematic name: 2-amino-4,5-dihydroxy-6-oxo-7-(phosphooxy)heptanoate hydro-lyase (cyclizing, 3-amino-4-hydroxybenzoate-forming)
Comments: Requires Mn2+ for maximum activity. The reaction is suggested to take place in several steps. Schiff base formation, double bond migration and dephosphorylation followed by ring opening and closing to form a pyrrolidine ring, and finally dehydration to form the product 3-amino-4-hydroxybenzoate. In the bacterium Streptomyces griseus the enzyme is involved in biosynthesis of grixazone, a yellow pigment that contains a phenoxazinone chromophore.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
1. Suzuki, H., Ohnishi, Y., Furusho, Y., Sakuda, S. and Horinouchi, S. Novel benzene ring biosynthesis from C3 and C4 primary metabolites by two enzymes. J. Biol. Chem. 281 (2006) 36944-36951. [PMID: 17003031]