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Structural characterization of MepB from Staphylococcus aureus reveals homology to endonucleases.

ABSTRACT: The MepRAB operon in Staphylococcus aureus has been identified to play a role in drug resistance. Although the functions of MepA and MepR are known, little information is available on the function of MepB. Here we report the X-ray structure of MepB to 2.1 Å revealing its structural similarity to the PD-(D/E)XK family of endonucleases. We further show that MepB binds DNA and RNA, with a higher affinity towards RNA and single stranded DNA than towards double stranded DNA. Notably, the PD-(D/E)XK catalytic active site residues are not conserved in MepB. MepB's association with a drug resistance operon suggests that it plays a role in responding to antimicrobials. This role is likely carried out through MepB's interactions with nucleic acids.

SUBMITTER: Agah S

PROVIDER: S-EPMC4005711 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature

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Structural characterization of MepB from Staphylococcus aureus reveals homology to endonucleases.

Agah Sayeh S Poulos Sandra S Banchs Christian C Faham Salem S

Protein science : a publication of the Protein Society 20140311 5

The MepRAB operon in Staphylococcus aureus has been identified to play a role in drug resistance. Although the functions of MepA and MepR are known, little information is available on the function of MepB. Here we report the X-ray structure of MepB to 2.1 Å revealing its structural similarity to the PD-(D/E)XK family of endonucleases. We further show that MepB binds DNA and RNA, with a higher affinity towards RNA and single stranded DNA than towards double stranded DNA. Notably, the PD-(D/E)XK c ...[more]

PMID: 24501097

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