Cloning of modular type I polyketide synthase genes from salinomycin producing strain of streptomyces albus

• Published in: Bioorganic & medicinal chemistry 2003-08, Vol.11 (16), p.3401-3405
• Main Authors: Izumikawa, Miho, Murata, Michio, Tachibana, Kazuo, Ebizuka, Yutaka, Fujii, Isao
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Antibiotics; Antibiotics (antibacterial agents, antifungal agents); Antibiotics, microbial producers, chemotherapic agents, antiseptics, disinfecting agents; Applied microbiology; Binding Sites; Biological and medical sciences; Biotechnology; Chromatography, High Pressure Liquid; Cloning, Molecular; Fundamental and applied biological sciences. Psychology; Genomic Library; Health. Pharmaceutical industry; Industrial applications and implications. Economical aspects; Microbiology; Molecular Sequence Data; Multienzyme Complexes - chemistry; Multienzyme Complexes - genetics; Mutation - genetics; Production of active biomolecules; Protein Structure, Tertiary; Pyrans - metabolism; Sequence Analysis, DNA; Streptomyces - classification; Streptomyces - enzymology; Streptomyces - genetics; Transformation, Bacterial
• ISSN: 0968-0896; 1464-3391
• DOI: 10.1016/S0968-0896(03)00337-7

Cloning of polyether polyketide synthase (PKS) genes for salinomycin biosynthesis was attempted from Streptomyces albus. Seven β-ketoacyl synthase (KS) core regions were obtained by PCR amplification using primers designed based on the conserved KS domains of type I PKSs. Using the KS fragment as a probe, screening of an S. albus genomic DNA library was carried out by colony hybridization. From the positive cosmid clone isolated, a 4.5-kb BamHI fragment was subcloned and sequenced. It showed high homology with bacterial type I PKSs and was deduced to code for KS, malonyl transferase, and ketoreductase motifs. By gene disruption with this 4.5-kb BamHI fragment, the cloned gene was shown to be a part of the salinomycin biosynthetic gene cluster of S. albus. Graphic