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A reported archaeal mechanosensitive channel is a structural homolog of MarR-like transcriptional regulators.

ABSTRACT: Several archaeal mechanosensitive (MS) channels have been reported, including one from Thermoplasma volcanium designated MscTV. Here, we report the crystal structure of MscTV at 1.6-A resolution. Unexpectedly, MscTV was found to be a water-soluble protein exhibiting a winged helix-turn-helix (wHTH) motif, which is the signature of the MarR (multiple antibiotic resistance regulator) family of transcriptional regulators. A cell-based osmotic downshock functional assay demonstrated that MscTV was unable to protect a knockout strain of Escherichia coli from hypoosmotic shock, further indicating that it does not function as a MS channel. We propose this protein be renamed MLPTv for MarR-like protein from T. volcanium.

SUBMITTER: Liu Z

PROVIDER: S-EPMC2867020 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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A reported archaeal mechanosensitive channel is a structural homolog of MarR-like transcriptional regulators.

Liu Zhenfeng Z Walton Troy A TA Rees Douglas C DC

Protein science : a publication of the Protein Society 20100401 4

Several archaeal mechanosensitive (MS) channels have been reported, including one from Thermoplasma volcanium designated MscTV. Here, we report the crystal structure of MscTV at 1.6-A resolution. Unexpectedly, MscTV was found to be a water-soluble protein exhibiting a winged helix-turn-helix (wHTH) motif, which is the signature of the MarR (multiple antibiotic resistance regulator) family of transcriptional regulators. A cell-based osmotic downshock functional assay demonstrated that MscTV was u ...[more]

PMID: 20162616

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