Function
Thioesterase; part of the gene cluster that mediates the biosynthesis of the lipopeptides W493 A and B (PubMed:25412204). W493 A and B consist of six amino acid residues D-allo-thr, L-Ala, D-Ala, L-Gln, D-Tyr, and L-Val/L-Ile linked to a 3-hydroxy-4-methyltetradecanoic acid polyketide chain (PubMed:25412204). The biosynthesis starts with formation of the linear polyketide chain by the highly reducing polyketide synthase PKS40 (PubMed:25412204). The gene cluster contains a putative acyl-CoA ligase (FPSE_09184) for formation of a CoA thioester polyketide. The thiol bond could be hydrolyzed by the putative thioesterase (FPSE_09186) and then accepted by the first T domain in module 1 of NRPS32 (PubMed:25412204). The second T domain is responsible for accepting a threonine, which is adenylated by the A domain and epimerized to the D-allo-threonine formed by the E domain. The five successive modules incorporate Ala, Ala, Gln, Tyr, and Val/Ile into the final product, which is released by cyclization (PubMed:25412204).