title: Structure and dynamics of polymyxin-resistance-associated response regulator PmrA in complex with promoter DNA.
abstract: PmrA, an OmpR/PhoB family response regulator, manages genes for antibiotic resistance. Phosphorylation of OmpR/PhoB response regulator induces the formation of a symmetric dimer in the N-terminal receiver domain (REC), promoting two C-terminal DNA-binding domains (DBDs) to recognize promoter DNA to elicit adaptive responses. Recently, determination of the KdpE-DNA complex structure revealed an REC-DBD interface in the upstream protomer that may be necessary for transcription activation. Here, we report the 3.2-Å-resolution crystal structure of the PmrA-DNA complex, which reveals a similar yet different REC-DBD interface. However, NMR studies show that in the DNA-bound state, two domains tumble separately and an REC-DBD interaction is transiently populated in solution. Reporter gene analyses of PmrA variants with altered interface residues suggest that the interface is not crucial for supporting gene expression. We propose that REC-DBD interdomain dynamics and the DBD-DBD interface help PmrA interact with RNA polymerase holoenzyme to activate downstream gene transcription.
authors.affiliation: Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, ROC.
authors.forename: Yuan-Chao
authors.initials: YC
authors.lastname: Lou
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan, ROC.
authors.forename: Tsai-Hsuan
authors.initials: TH
authors.lastname: Weng
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan, ROC.
authors.forename: Yi-Chuan
authors.initials: YC
authors.lastname: Li
authors.affiliation: Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, ROC.
authors.forename: Yi-Fen
authors.initials: YF
authors.lastname: Kao
authors.affiliation: Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 300, Taiwan, ROC.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Lin
authors.affiliation: Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 300, Taiwan, ROC.
authors.forename: Hwei-Ling
authors.initials: HL
authors.lastname: Peng
authors.affiliation: Institute of Biochemistry, National Chung Hsing University, Taichung 40227, Taiwan, ROC.|Agricultural Biotechnology Center, National Chung Hsing University, Taichung 40227, Taiwan, ROC.
authors.forename: Shan-Ho
authors.initials: SH
authors.lastname: Chou
authors.affiliation: Institute of Molecular Biology, Academia Sinica, Taipei 115, Taiwan, ROC.
authors.forename: Chwan-Deng
authors.initials: CD
authors.lastname: Hsiao
authors.affiliation: Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, ROC.|Agricultural Biotechnology Center, National Chung Hsing University, Taichung 40227, Taiwan, ROC.
authors.forename: Chinpan
authors.initials: C
authors.lastname: Chen
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D015964:Gene Expression Regulation, Bacterial; D007711:Klebsiella pneumoniae / Q000737:chemistry / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D011113:Polymyxins / Q000494:pharmacology*; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D015534:Trans-Activators / Q000737:chemistry / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D011113:Polymyxins; D015534:Trans-Activators; C081902:pmrA protein, Bacteria