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Role of the Mce1 transporter in the lipid homeostasis of Mycobacterium tuberculosis.

ABSTRACT: Tuberculosis is one of the leading causes of mortality throughout the world. Mycobacterium tuberculosis, the causative agent of human tuberculosis, has developed several strategies involving proteins and other compounds known collectively as virulence factors to subvert human host defences and invade the human host. The Mce proteins are among these virulence-related proteins and are encoded by the mce1, mce2, mce3 and mce4 operons in the genome of M. tuberculosis. It has been proposed that these operons encode ABC-like lipid transporters; however, the nature of their substrates has only been revealed in the case of the Mce4 proteins. Here we found that the knockout of the mce1 operon alters the lipid profile of M. tuberculosis H37Rv and the uptake of palmitic acid. Thin layer chromatography and liquid chromatography-mass spectrometry analysis showed that the mce1 mutant accumulates more mycolic acids than the wild type and complemented strains. Interestingly, this accumulation of mycolic acid is exacerbated when bacteria are cultured in the presence of palmitic acid or arachidonic acid. These results suggest that the mce1 operon may serve as a mycolic acid re-importer.

SUBMITTER: Forrellad MA

PROVIDER: S-EPMC3951760 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Role of the Mce1 transporter in the lipid homeostasis of Mycobacterium tuberculosis.

Forrellad Marina Andrea MA McNeil Michael M Santangelo María de la Paz Mde L Blanco Federico Carlos FC García Elizabeth E Klepp Laura Inés LI Huff Jason J Niederweis Michael M Jackson Mary M Bigi Fabiana F

Tuberculosis (Edinburgh, Scotland) 20140102 2

Tuberculosis is one of the leading causes of mortality throughout the world. Mycobacterium tuberculosis, the causative agent of human tuberculosis, has developed several strategies involving proteins and other compounds known collectively as virulence factors to subvert human host defences and invade the human host. The Mce proteins are among these virulence-related proteins and are encoded by the mce1, mce2, mce3 and mce4 operons in the genome of M. tuberculosis. It has been proposed that these ...[more]

PMID: 24440549

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Dataset Information

Role of the Mce1 transporter in the lipid homeostasis of Mycobacterium tuberculosis.

Publications

Role of the Mce1 transporter in the lipid homeostasis of Mycobacterium tuberculosis.

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