title: Enhancing the modularity of the modular polyketide synthases: transacylation in modular polyketide synthases catalyzed by malonyl-CoA:ACP transacylase.
abstract: Selective incorporation of extender units in modular polyketide synthases is primarily controlled by acyl transferase (AT) domains. The AT domains catalyze transacylation of the extender unit from acyl-CoA to the phosphopantetheine arm of an acyl carrier protein (ACP) domain in the same module. New methods that can modulate the extender unit specificity of individual modules with minimal structural or kinetic perturbations in the engineered module are desirable for the efficient biosynthesis of novel natural product analogues. We have demonstrated that transacylation of malonyl groups onto an AT-null form of a mutant modular polyketide synthase by malonyl-CoA:ACP transacylase is an effective strategy for the engineered biosynthesis of site specifically modified polyketides. Using this strategy, 6-deoxyerythronolide B synthase was engineered to exclusively produce 2-desmethyl-6-deoxyerythronolide B. The productivity of the modified system was comparable to that of the wild-type synthase in vitro and in vivo.
authors: Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA.
authors: Pawan
authors: P
authors: Kumar
authors: Andrew T
authors: AT
authors: Koppisch
authors: David E
authors: DE
authors: Cane
authors: Chaitan
authors: C
authors: Khosla
mesh_terms: D000213:Acyl Carrier Protein / Q000737:chemistry / Q000378:metabolism; D051080:Acyl-Carrier Protein S-Malonyltransferase; D000217:Acyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004917:Erythromycin / Q000031:analogs & derivatives / Q000096:biosynthesis; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D029968:Escherichia coli Proteins; D054889:Fatty Acid Synthase, Type II; D009097:Multienzyme Complexes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015202:Protein Engineering / Q000379:methods; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013302:Streptomyces / Q000201:enzymology
chemical_list: D000213:Acyl Carrier Protein; D029968:Escherichia coli Proteins; D009097:Multienzyme Complexes; D011994:Recombinant Proteins; D004917:Erythromycin; D000217:Acyltransferases; D051080:Acyl-Carrier Protein S-Malonyltransferase; C494968:fabD protein, E coli; D054889:Fatty Acid Synthase, Type II