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Transcriptional regulation of fatty acid biosynthesis in Lactococcus lactis.

ABSTRACT: Here we study the influence of the putative fatty acid biosynthesis (FAB) regulator FabT (originally called RmaG [Llmg_1788]) on gene transcription in Lactococcus lactis MG1363. A strain with a knockout mutation of the putative regulator was constructed, and its transcriptome was compared to that of the wild-type strain. Almost all FAB genes were significantly upregulated in the knockout. Using electrophoretic mobility shift assays (EMSAs) and DNase I footprinting, the binding motif of the regulator and the binding locations in the genome were characterized. Fatty acid composition analysis revealed that a strain lacking FabT contained significantly more saturated acyl chains in its phospholipids. This observation demonstrates that the vital pathway of FAB in L. lactis is regulated by the repressor FabT.

SUBMITTER: Eckhardt TH

PROVIDER: S-EPMC3571327 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Transcriptional regulation of fatty acid biosynthesis in Lactococcus lactis.

Eckhardt Tom H TH Skotnicka Dorota D Kok Jan J Kuipers Oscar P OP

Journal of bacteriology 20121228 5

Here we study the influence of the putative fatty acid biosynthesis (FAB) regulator FabT (originally called RmaG [Llmg_1788]) on gene transcription in Lactococcus lactis MG1363. A strain with a knockout mutation of the putative regulator was constructed, and its transcriptome was compared to that of the wild-type strain. Almost all FAB genes were significantly upregulated in the knockout. Using electrophoretic mobility shift assays (EMSAs) and DNase I footprinting, the binding motif of the regul ...[more]

PMID: 23275247

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