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Dapdiamides, tripeptide antibiotics formed by unconventional amide ligases.

ABSTRACT: Construction of a genomic DNA library from Pantoea agglomerans strain CU0119 and screening against the plant pathogen Erwinia amylovora yielded a new family of antibiotics, dapdiamides A-E (1-5). The structures were established through 2D-NMR experiments and mass spectrometry, as well as the synthesis of dapdiamide A (1). Transposon mutagenesis of the active cosmid allowed identification of the biosynthetic gene cluster. The dapdiamide family's promiscuous biosynthetic pathway contains two unconventional amide ligases that are predicted to couple its constituent monomers.

SUBMITTER: Dawlaty J

PROVIDER: S-EPMC2846032 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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Dapdiamides, tripeptide antibiotics formed by unconventional amide ligases.

Dawlaty Jessica J Zhang Xiaorong X Fischbach Michael A MA Clardy Jon J

Journal of natural products 20100301 3

Construction of a genomic DNA library from Pantoea agglomerans strain CU0119 and screening against the plant pathogen Erwinia amylovora yielded a new family of antibiotics, dapdiamides A-E (1-5). The structures were established through 2D-NMR experiments and mass spectrometry, as well as the synthesis of dapdiamide A (1). Transposon mutagenesis of the active cosmid allowed identification of the biosynthetic gene cluster. The dapdiamide family's promiscuous biosynthetic pathway contains two uncon ...[more]

PMID: 20041689

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