Accepted name: grixazone synthase
Reaction: 2 3-amino-4-hydroxybenzoate + N-acetyl-L-cysteine + 2 O2 = grixazone B + 4 H2O + CO2
Glossary: grixazone B = 8-amino-9-(N-acetyl-L-cystein-S-yl)-7-oxo-7H-phenoxazine-2-carboxylic acid
Other name(s): GriF
Systematic name: 3-amino-4-hydroxybenzoate:N-acetyl-L-cysteine:oxygen oxidoreductase
Comments: A type 3 multi copper protein. The enzyme, isolated from the bacterium Streptomyces griseus, catalyses an 8 electron oxidation. Activation of the enzyme requires a copper chaperone (GriE). It also acts on 3-amino-4-hydroxybenzaldehyde, giving grixazone A. The second aldehyde group is presumably lost as formate. The enzyme also catalyses the reaction of EC o-aminophenol oxidase.
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]
2.  Le Roes-Hill, M., Goodwin, C. and Burton, S. Phenoxazinone synthase: what’s in a name. Trends Biotechnol. 27 (2009) 248–258. [PMID: 19268377]
[EC created 2014]