N-terminal and C-terminal aromatase/cyclase domains of Streptomyces rimosus OtcD1 and related domains
This family includes the N- and C- terminal aromatase/cyclase (ARO/CYC) domains of Streptomyces rimosus OtcD1 and related domains. It belongs to the SRPBCC (START/RHO_alpha_C/PITP/Bet_v1/CoxG/CalC) domain superfamily of proteins that bind hydrophobic ligands. SRPBCC domains have a deep hydrophobic ligand-binding pocket. ARO/CYC domains participate in the diversification of aromatic polyketides by promoting polyketide cyclization. They occur in two architectural forms, didomain and monodomain. Didomain aromatase/cyclases (ARO/CYCs), contain two ARO/CYC domains, and are associated with C7-C12 first ring cyclized polyketides. Streptomyces rimosus OtcD1 is a didomain ARO/CYC. The polyketide Oxytetracycline (OTC) is a broad spectrum antibiotic made by Streptomyces rimosus. The gene encoding OtcD1 is part of oxytetracycline (OTC) gene cluster. Disruption of this gene results in the production of novel polyketides having shorter chain lengths (by up to 10 carbons) than OTC. Monodomain ARO/CYCs have a single ARO/CYC domain, and are often associated with C9-C14 first ring cyclizations, these latter domains belong to a different subfamily in the SRPBCC superfamily.