title: Structural insights into Escherichia coli polymyxin B resistance protein D with X-ray crystallography and small-angle X-ray scattering.
abstract: BACKGROUND
  Polymyxin B resistance protein D (PmrD) plays a key role in the polymyxin B-resistance pathway, as it is the signaling protein that can act as a specific connecter between PmrA/PmrB and PhoP/PhoQ. We conducted structural analysis to characterize Escherichia coli (E. coli) PmrD, which exhibits different features compared with PmrD in other bacteria.
  
  
  RESULTS
  The X-ray crystal structure of E. coli PmrD was determined at a 2.00 Å resolution, revealing novel information such as the unambiguous secondary structures of the protein and the presence of a disulfide bond. Furthermore, various assays such as native gel electrophoresis, surface plasmon resonance (SPR), size-exclusion chromatography, dynamic light scattering (DLS), and small-angle X-ray scattering (SAXS) measurements, were performed to elucidate the structural and functional role of the internal disulfide bond in E. coli PmrD.
  
  
  CONCLUSIONS
  The structural characteristics of E. coli PmrD were clearly identified via diverse techniques. The findings help explain the different protective mechanism of E. coli compared to other Gram-negative bacteria.
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 790-784, South Korea. jhhsst@postech.ac.kr.
authors.forename: Hunho
authors.initials: H
authors.lastname: Jo
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 790-784, South Korea. eyjeong@postech.ac.kr.
authors.forename: Eui Young
authors.initials: EY
authors.lastname: Jeong
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 790-784, South Korea. sung0214@postech.ac.kr.
authors.forename: Jinseong
authors.initials: J
authors.lastname: Jeon
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology, 77, Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk, 790-784, South Korea. ciban@postech.ac.kr.
authors.forename: Changill
authors.initials: C
authors.lastname: Ban
mesh_terms: D018360:Crystallography, X-Ray; D004220:Disulfides / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D017433:Protein Structure, Secondary; D053838:Scattering, Small Angle
chemical_list: D004220:Disulfides; D029968:Escherichia coli Proteins; C523605:PmrD protein, E coli