Dataset Information

Partial Saturation of Menaquinone in Mycobacterium tuberculosis: Function and Essentiality of a Novel Reductase, MenJ.

ABSTRACT: Menaquinone (MK) with partially saturated isoprenyl moieties is found in a wide range of eubacteria and Archaea. In many Gram-positive organisms, including mycobacteria, it is the double bond found in the ?-isoprene unit that is reduced. Mass spectral characterization of menaquinone from mycobacterial knockout strains and heterologous expression hosts demonstrates that Rv0561c (designated menJ) encodes an enzyme which reduces the ?-isoprene unit of menaquinone in Mycobacterium tuberculosis, forming the predominant form of menaquinone found in mycobacteria. MenJ is highly conserved in mycobacteria species but is not required for growth in culture. Disruption of menJ reduces mycobacterial electron transport efficiency by 3-fold, but mycobacteria are able to maintain ATP levels by increasing the levels of the total menaquinone in the membrane; however, MenJ is required for M. tuberculosis survival in host macrophages. Thus, MK with partially hydrogenated isoprenyl moieties represents a novel virulence factor and MenJ is a contextually essential enzyme and a potential drug target in pathogenic mycobacteria and other Gram-positive pathogens.

SUBMITTER: Upadhyay A

PROVIDER: S-EPMC4582327 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Publications

Partial Saturation of Menaquinone in Mycobacterium tuberculosis: Function and Essentiality of a Novel Reductase, MenJ.

Upadhyay Ashutosh A Fontes Fabio L FL Gonzalez-Juarrero Mercedes M McNeil Michael R MR Crans Debbie C DC Jackson Mary M Crick Dean C DC

ACS central science 20150812 6

Menaquinone (MK) with partially saturated isoprenyl moieties is found in a wide range of eubacteria and Archaea. In many Gram-positive organisms, including mycobacteria, it is the double bond found in the β-isoprene unit that is reduced. Mass spectral characterization of menaquinone from mycobacterial knockout strains and heterologous expression hosts demonstrates that Rv0561c (designated menJ) encodes an enzyme which reduces the β-isoprene unit of menaquinone in Mycobacterium t ...[more]

PMID: 26436137

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Dataset Information

Partial Saturation of Menaquinone in Mycobacterium tuberculosis: Function and Essentiality of a Novel Reductase, MenJ.

Publications

Partial Saturation of Menaquinone in <i>Mycobacterium tuberculosis</i>: Function and Essentiality of a Novel Reductase, MenJ.

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