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Characterization of the lnmKLM genes unveiling key intermediates for ?-alkylation in leinamycin biosynthesis.

ABSTRACT: Leinamycin (LNM, 1) biosynthesis is proposed to involve ?-alkylation of the polyketide intermediate, catalyzed by LnmKLM. Inactivation of lnmK, lnmL, or lnmM afforded mutant strains that accumulated LNM K-1 (2), K-2 (3), K-3 (4), and isomers LNM K-1' (5), K-2' (6), and K-3' (7) whose polyketide origin was established by feeding experiments with sodium [1-(13)C]acetate. These findings confirm the indispensability of LnmKLM in 1 biosynthesis and suggest that ?-alkylation proceeds on the growing polyketide intermediate while bound to the LNM polyketide synthase.

SUBMITTER: Huang Y

PROVIDER: S-EPMC3074603 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Characterization of the lnmKLM genes unveiling key intermediates for β-alkylation in leinamycin biosynthesis.

Huang Yong Y Huang Sheng-Xiong SX Ju Jianhua J Tang Gongli G Liu Tao T Shen Ben B

Organic letters 20101230 3

Leinamycin (LNM, 1) biosynthesis is proposed to involve β-alkylation of the polyketide intermediate, catalyzed by LnmKLM. Inactivation of lnmK, lnmL, or lnmM afforded mutant strains that accumulated LNM K-1 (2), K-2 (3), K-3 (4), and isomers LNM K-1' (5), K-2' (6), and K-3' (7) whose polyketide origin was established by feeding experiments with sodium [1-(13)C]acetate. These findings confirm the indispensability of LnmKLM in 1 biosynthesis and suggest that β-alkylation proceeds on the growing po ...[more]

PMID: 21192727

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