A gene cluster involved in nogalamycin biosynthesis fromStreptomyces nogalater: sequence analysis and complementation of early-block mutations in the anthracycline pathway
- 191 Downloads
We have analyzed an anthracycline biosynthesis gene cluster fromStreptomyces nogalater. Based on sequence analysis, a contiguous region of 11 kb is deduced to include genes for the early steps in anthracycline biosynthesis, a regulatory gene (snoA) promoting the expression of the biosynthetic genes, and at least one gene whose product might have a role in modification of the glycoside moiety. The three ORFs encoding a minimal polyketide synthase (PKS) are separated from the regulatory gene (snoA) by a comparatively AT-rich region (GC content 60%). Subfragments of the DNA region were transferred toStreptomyces galilaeus mutants blocked in aclacinomycin biosynthesis, and to a regulatory mutant ofS. nogalater. TheS. galilaeus mutants carrying theS. nogalater minimal PKS genes produced auramycinone glycosides, demonstrating replacement of the starter unit for polyketide biosynthesis. The product ofsnoA seems to be needed for expression of at least the genes for the minimal PKS.
Key wordsStreptomyces Nogalamycin Anthracycline Polyketide synthase
Unable to display preview. Download preview PDF.
- Fu H, Ebert-Khosla S, Hopwood DA, Khosla C (1994) Engineered biosynthesis of novel polyketides: dissection of the catalytic specificity of theact ketoreductase. J Am Chem Soc 116:4166–4170Google Scholar
- Fujiwara A, Hoshino T, Tazoe M (1980) Process to produce aclacinomycins A and B: U.S. Patent 4 375 511. Published 1.3.1983, priority 27.10.1980Google Scholar
- Hopwood DA, Bibb MJ, Chater KF, Kieser T, Bruton CJ, Kieser HM, Lydiate DJ, Smith CP, Ward JM, Schrempf H (1985) Genetic manipulation ofStreptomyces: a laboratory manual. The John Innes Foundation, NorwichGoogle Scholar
- Malpartida F, Hallam SE, Kieser HM, Motamedi H, Hutchinson CR, Butler MJ, Sugden DA, Warren M, McKillop C, Bailey CR, Humphreys GO, Hopwood DA (1987) Homology betweenStreptomyces genes coding for synthesis of different polyketides and its use to clone antibiotic biosynthetic genes. Nature 325:818–821PubMedGoogle Scholar
- McDaniel R, Ebert-Khosla S, Hopwood DA, Khosla C (1994b) Engineered biosynthesis of novel polyketides:actVII andactIV genes encode aromatase and cyclase enzymes, respectively. J Am Chem Soc 116:10855–10859Google Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual (2nd edn). Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New YorkGoogle Scholar
- Summers RG, Wendt-Pienkowski E, Motamedi H, Hutchinson CR (1993) ThetcmVI region of the tetracenomycin C biosynthetic gene cluster ofStreptomyces glaucescens encodes the tetracenomycin F1 monooxygenase, tetracenomycin F2 cyclase, and, most likely, a second cyclase. J Bacteriol 175:7571–7580PubMedGoogle Scholar
- Wiley PF, MacKellar FA, Caron EL, Kelly RB (1968) Isolation, characterization and degradation of nogalamycin. Tetrahedron Lett 663–668Google Scholar