EC |
1.10.3.15 |
Accepted name: |
grixazone synthase |
Reaction: |
2 3-amino-4-hydroxybenzoate + N-acetyl-L-cysteine + 2 O2 = grixazone B + 4 H2O + CO2 |
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For diagram of grixazone biosynthesis, click here |
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 1.10.3.4 o-aminophenol oxidase. |
Links to other databases: |
BRENDA, EXPASY, KEGG, MetaCyc |
References: |
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. [DOI] [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. [DOI] [PMID: 19268377] |
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[EC 1.10.3.15 created 2014] |
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EC |
4.1.99.20 |
Accepted name: |
3-amino-4-hydroxybenzoate synthase |
Reaction: |
2-amino-4,5-dihydroxy-6-oxo-7-(phosphooxy)heptanoate = 3-amino-4-hydroxybenzoate + phosphate + 2 H2O |
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For diagram of grixazone biosynthesis, 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 |
References: |
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. [DOI] [PMID: 17003031] |
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[EC 4.1.99.20 created 2013, modified 2016] |
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