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Crystal structure of the Mycobacterium tuberculosis transcriptional regulator Rv0302
Author(s) -
Chou TsungHan,
Delmar Jared A.,
Wright Catherine C.,
Kumar Nitin,
Radhakrishnan Abhijith,
Doh Julia K.,
Licon Meredith H.,
Bolla Jani Reddy,
Lei HsiangTing,
Rajashankar Kanagalaghatta R.,
Su ChihChia,
Purdy Georgiana E.,
Yu Edward W.
Publication year - 2015
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1002/pro.2802
Subject(s) - tetr , biology , electrophoretic mobility shift assay , mycobacterium tuberculosis , isothermal titration calorimetry , regulator , biochemistry , microbiology and biotechnology , genetics , gene , repressor , transcription factor , tuberculosis , medicine , pathology
Mycobacterium tuberculosis is a pathogenic bacterial species, which is neither Gram positive nor Gram negative. It has a unique cell wall, making it difficult to kill and conferring resistance to antibiotics that disrupt cell wall biosynthesis. Thus, the mycobacterial cell wall is critical to the virulence of these pathogens. Recent work shows that the mycobacterial membrane protein large (MmpL) family of transporters contributes to cell wall biosynthesis by exporting fatty acids and lipidic elements of the cell wall. The expression of the Mycobacterium tuberculosis MmpL proteins is controlled by a complicated regulatory network system. Here we report crystallographic structures of two forms of the TetR‐family transcriptional regulator Rv0302, which participates in regulating the expression of MmpL proteins. The structures reveal a dimeric, two‐domain molecule with architecture consistent with the TetR family of regulators. Comparison of the two Rv0302 crystal structures suggests that the conformational changes leading to derepression may be due to a rigid body rotational motion within the dimer interface of the regulator. Using fluorescence polarization and electrophoretic mobility shift assays, we demonstrate the recognition of promoter and intragenic regions of multiple mmpL genes by this protein. In addition, our isothermal titration calorimetry and electrophoretic mobility shift experiments indicate that fatty acids may be the natural ligand of this regulator. Taken together, these experiments provide new perspectives on the regulation of the MmpL family of transporters.