Rationally Designed Glycosylated Premithramycins: Hybrid Aromatic Polyketides Using Genes from Three Different Biosynthetic Pathways

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• 作者：Axel Trefzer ; Gloria Blanco ; Lily Remsing ; Eva K&uuml ; nzel ; Uwe Rix ; Fredilyn Lipata ; Alfredo F. Brañ ; a ; Carmen Mé ; ndez ; J&uuml ; rgen Rohr ; Andreas Bechthold ; and José ; A. Salas
• 刊名：Journal of the American Chemical Society
• 出版年：2002
• 出版时间：May 29, 2002
• 年：2002
• 卷：124
• 期：21
• 页码：6056 - 6062
• 全文大小：110K
• 年卷期：v.124,no.21(May 29, 2002)
• ISSN：1520-5126

文摘

Heterologous expression of the urdGT2 gene from the urdamycin producer Streptomyces fradiaeTü2717, which encodes a C-glycosyltransferase, into mutants of the mithramycin producer Streptomycesargillaceus, in which either one or all glycosyltransferases were inactivated, yielded four novel C-glycosylatedpremithramycin-type molecules. Structure elucidation revealed these to be 9-C-olivosylpremithramycinone,9-C-mycarosylpremithramycinone, and their respective 4-O-demethyl analogues. In another experiment,both the urdGT2 gene from S. fradiae and the lanGT1 gene from S. cyanogenus, were coexpressed intoa S. argillaceus mutant lacking the MtmGIV glycosyltransferase. This experiment, in which genes fromthree different organisms were combined, resulted in the production of 9-C-(olivo-1-4-olivosyl)premithramycinone. These results prove the unique substrate flexibility of the C-glycosyltransferase UrdGT2, whichtolerates not only a variety of sugar-donor substrates, but also various acceptor substrates. The five newhybrid products also represent the first compounds, in which sugars were attached to a position that isnormally unglycosylated. The successful combination of two glycosyltransferases in the latter experimentproves that the design of saccharide side chains by combinatorial biosynthetic methods is possible.