Repositioning of a Domain in a Modular Polyketide Synthase to Promote Specific Chain Cleavage

• Published in: Science (American Association for the Advancement of Science) Vol. 268; no. 5216; pp. 1487 - 1489
• Main Authors: Cortes, Jesus, Kirsten E. H. Wiesmann, Roberts, Gareth A., Murray J. B. Brown, Staunton, James, Leadlay, Peter F.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for the Advancement of Science 09.06.1995; American Association for the Advancement of Science; The American Association for the Advancement of Science
• Subjects: Acetates; Active sites; Analytical, structural and metabolic biochemistry; Antibiotics; Bacteria; Base Sequence; Binding Sites; Biological and medical sciences; Biosynthesis; Carrier proteins; Catalysts; Chemistry; Cloning, Molecular; Codons; Enzymes; Enzymes and enzyme inhibitors; Erythromycin - biosynthesis; Fundamental and applied biological sciences. Psychology; Genes; Genes, Bacterial; Genetic aspects; Genetic mutation; Genetic Vectors; Lactones; Miscellaneous; Molecular Sequence Data; Multienzyme Complexes - chemistry; Multienzyme Complexes - genetics; Multienzyme Complexes - metabolism; Mutation; Organic Chemistry; Plasmids; Polyketides; Protein Engineering; Saccharopolyspora - enzymology; Saccharopolyspora - genetics; Saccharopolyspora erythraea; Streptomyces; Transformation, Genetic; Antibiotic; Saccharopolyspora erythraea; Multienzyme complex; Structure activity relation; Enzyme; Bacteria; Actinomycetes; Pseudonocardiaceae; Erythromycin; Mutation; Antibacterial agent
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.7770773

Macrocyclic polyketides exhibit an impressive range of medically useful activities, and there is great interest in manipulating the genes that govern their synthesis. The 6-deoxyerythronolide B synthase (DEBS) of Saccharopolyspora erythraea, which synthesizes the aglycone core of the antibiotic erythromycin A, has been modified by repositioning of a chain-terminating cyclase domain to the carboxyl-terminus of DEBS1, the multienzyme that catalyzes the first two rounds of polyketide chain extension. The resulting mutant markedly accelerates formation of the predicted triketide lactone, compared to a control in which the repositioned domain is inactive. Repositioning of the cyclase should be generally useful for redirecting polyketide synthesis to obtain polyketides of specified chain lengths.