title: Structural basis of a physical blockage mechanism for the interaction of response regulator PmrA with connector protein PmrD from Klebsiella pneumoniae.
abstract: In bacteria, the two-component system is the most prevalent for sensing and transducing environmental signals into the cell. The PmrA-PmrB two-component system, responsible for sensing external stimuli of high Fe(3+) and mild acidic conditions, can control the genes involved in lipopolysaccharide modification and polymyxin resistance in pathogens. In Klebsiella pneumoniae, the small basic connector protein PmrD protects phospho-PmrA and prolongs the expression of PmrA-activated genes. We previously determined the phospho-PmrA recognition mode of PmrD. However, how PmrA interacts with PmrD and prevents its dephosphorylation remains unknown. To address this question, we solved the x-ray crystal structure of the N-terminal receiver domain of BeF3(-)-activated PmrA (PmrA(N)) at 1.70 Å. With this structure, we applied the data-driven docking method based on NMR chemical shift perturbation to generate the complex model of PmrD-PmrA(N), which was further validated by site-directed spin labeling experiments. In the complex model, PmrD may act as a blockade to prevent phosphatase from contacting with the phosphorylation site on PmrA.
authors.affiliation: From the Institutes of Biomedical Sciences and.
authors.forename: Shih-Chi
authors.initials: SC
authors.lastname: Luo
authors.affiliation: From the Institutes of Biomedical Sciences and.
authors.forename: Yuan-Chao
authors.initials: YC
authors.lastname: Lou
authors.affiliation: From the Institutes of Biomedical Sciences and.
authors.forename: Mahalingam
authors.initials: M
authors.lastname: Rajasekaran
authors.affiliation: Molecular Biology, Academia Sinica, Taipei 115, Taiwan and.
authors.forename: Yi-Wei
authors.initials: YW
authors.lastname: Chang
authors.affiliation: Molecular Biology, Academia Sinica, Taipei 115, Taiwan and.
authors.forename: Chwan-Deng
authors.initials: CD
authors.lastname: Hsiao
authors.affiliation: From the Institutes of Biomedical Sciences and; Agricultural Biotechnology Center, National Chung Hsing University, Taichung 40227, Taiwan. Electronic address: bmchinp@ibms.sinica.edu.tw.
authors.forename: Chinpan
authors.initials: C
authors.lastname: Chen
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D018360:Crystallography, X-Ray; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D007501:Iron / Q000737:chemistry* / Q000378:metabolism; D007711:Klebsiella pneumoniae / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D010766:Phosphorylation / Q000502:physiology; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary
chemical_list: D001426:Bacterial Proteins; C081902:pmrA protein, Bacteria; D007501:Iron
keywords: Drug Resistance; Molecular Docking; NMR; Protein-protein Interaction; Receiver Domain; Response Regulator; Signal Transduction; Site-directed Mutagenesis; Site-directed Spin Labeling; Two-component System