Pikromycin polyketide synthase component PikAIV (PikAIV)

Pikromycin polyketide synthase component PikAIV (PikAIV) is the final module (module 6) of the modular type I polyketide synthase responsible for the biosynthesis of the macrolactone antibiotic pikromycin and related compounds, including narbomycin, methymycin, and neomethymycin[6][1]. PikAIV is a large, multi-domain enzyme that catalyzes the extension, modification, and release of polyketide intermediates, functioning by a series of integrated catalytic domains (including ketosynthase, acyltransferase, enoylreductase, ketoreductase, and an acyl carrier protein, ending with a thioesterase domain)[1]. PikAIV and the other PikA modules act in an assembly-line fashion, with substrates transferred between modules via docking domains[1][2]. The thioesterase domain in PikAIV is responsible for the final cyclization/release step, leading to the formation of macrolactone rings that are precursors to clinically important antibiotics[6][1]. PikAIV is found in Streptomyces venezuelae. It is not considered a therapeutic target in the sense used for human enzymes or receptors, but is of great interest for biosynthetic engineering and antibiotic production[1][6][2].

Other names

Type I polyketide synthase PikAIVPikromycin PKS module 6PKS PikAIVModular polyketide synthase PikAIV