Reaction: anthraniloyl-CoA + malonyl-CoA = 2-(aminobenzoyl)acetyl-CoA + CoA + CO2 (overall reaction)
(1a) anthraniloyl-CoA + L-cysteinyl-[PqsD protein] = S-anthraniloyl-L-cysteinyl-[PqsD protein] + CoA
(1b) S-anthraniloyl-L-cysteinyl-[PqsD protein] + malonyl-CoA = 2-(aminobenzoyl)acetyl-CoA + CO2 + L-cysteinyl-[PqsD protein]
Glossary: anthraniloyl-CoA = 2-aminobenzoyl-CoA
Other name(s): pqsD (gene name)
Systematic name: anthraniloyl-CoA:malonyl-CoA anthraniloyltransferase
Comments: The enzyme, characterized from the bacterium Pseudomonas aeruginosa, participates in the synthesis of the secondary metabolites 2-heptyl-3-hydroxy-4(1H)-quinolone and 4-hydroxy-2(1H)-quinolone. The enzyme transfers an anthraniloyl group from anthraniloyl-CoA to an internal L-cysteine residue, followed by its transfer to malonyl-CoA to produce a short-lived product that can cyclize spontaneously to form 4-hydroxy-2(1H)-quinolone. However, when EC 3.1.2.32, 2-aminobenzoylacetyl-CoA thiesterase, is present, it removes the CoA moiety from the product, forming the stable 2-aminobenzoylacetate.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:
References:
1. Bera, A.K., Atanasova, V., Robinson, H., Eisenstein, E., Coleman, J.P., Pesci, E.C. and Parsons, J.F. Structure of PqsD, a Pseudomonas quinolone signal biosynthetic enzyme, in complex with anthranilate. Biochemistry 48 (2009) 8644-8655. [PMID: 19694421]
2. Dulcey, C.E., Dekimpe, V., Fauvelle, D.A., Milot, S., Groleau, M.C., Doucet, N., Rahme, L.G., Lepine, F. and Deziel, E. The end of an old hypothesis: the Pseudomonas signaling molecules 4-hydroxy-2-alkylquinolines derive from fatty acids, not 3-ketofatty acids. Chem. Biol. 20 (2013) 1481-1491. [PMID: 24239007]
3. Drees, S.L. and Fetzner, S. PqsE of Pseudomonas aeruginosa acts as pathway-specific thioesterase in the biosynthesis of alkylquinolone signaling molecules. Chem. Biol. 22 (2015) 611-618. [PMID: 25960261]