Characterization of a functional C-terminus of the Mycobacterium tuberculosis MtrA responsible for both DNA binding and interaction with its two-component partner protein, MtrB.
Virulence in pathogenic bacteria is due in part to the action of two-component systems. However, in the human pathogen Mycobacterium tuberculosis, the molecular mechanisms underlying these systems are as yet unclear. In this study, MtrA was shown to contain a functional C-terminus and also to have Ca(2+) as its preferred cofactor for DNA binding. Further mutation experiments demonstrated that the C-terminus of MtrA was responsible for specific interactions with the target DNA motif and also with its partner protein, MtrB. The physical interaction between MtrA and MtrB inhibited DNA binding by MtrA. These findings yield critical information about the unique regulatory mechanisms of the essential MtrAB two-component system in this pathogen.
Li
Yuqing
Y
National Key Laboratory of Agricultural Microbiology, Center for Proteomics Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
Zeng
Jumei
J
He
Zheng-Guo
ZG
D000595:Amino Acid Sequence; D002118:Calcium / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000472:pathogenicity; D010766:Phosphorylation; D020349:Surface Plasmon Resonance; D020798:Two-Hybrid System Techniques; D014774:Virulence / Q000502:physiology
D004268:DNA-Binding Proteins; D002118:Calcium