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Pseudoglycosyltransferase catalyzes nonglycosidic C-N coupling in validamycin a biosynthesis.

ABSTRACT: Glycosyltransferases are ubiquitous in nature. They catalyze a glycosidic bond formation between sugar donors and sugar or nonsugar acceptors to produce oligo/polysaccharides, glycoproteins, glycolipids, glycosylated natural products, and other sugar-containing entities. However, a trehalose 6-phosphate synthase-like protein has been found to catalyze an unprecedented nonglycosidic C-N bond formation in the biosynthesis of the aminocyclitol antibiotic validamycin A. This dedicated 'pseudoglycosyltransferase' catalyzes a condensation between GDP-valienol and validamine 7-phosphate to give validoxylamine A 7'-phosphate with net retention of the 'anomeric' configuration of the donor cyclitol in the product. The enzyme operates in sequence with a phosphatase, which dephosphorylates validoxylamine A 7'-phosphate to validoxylamine A.

SUBMITTER: Asamizu S

PROVIDER: S-EPMC3162038 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Pseudoglycosyltransferase catalyzes nonglycosidic C-N coupling in validamycin a biosynthesis.

Asamizu Shumpei S Yang Jongtae J Almabruk Khaled H KH Mahmud Taifo T

Journal of the American Chemical Society 20110718 31

Glycosyltransferases are ubiquitous in nature. They catalyze a glycosidic bond formation between sugar donors and sugar or nonsugar acceptors to produce oligo/polysaccharides, glycoproteins, glycolipids, glycosylated natural products, and other sugar-containing entities. However, a trehalose 6-phosphate synthase-like protein has been found to catalyze an unprecedented nonglycosidic C-N bond formation in the biosynthesis of the aminocyclitol antibiotic validamycin A. This dedicated 'pseudoglycosy ...[more]

PMID: 21766819

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Nucleotidylation of unsaturated carbasugar in validamycin biosynthesis.

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Gene cluster responsible for validamycin biosynthesis in Streptomyces hygroscopicus subsp. jinggangensis 5008.

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