title: Immunoreactivity of the AAA+ chaperone ClpB from Leptospira interrogans with sera from Leptospira-infected animals.
abstract: Leptospira interrogans is a spirochaete responsible for leptospirosis in mammals. The molecular mechanisms of the Leptospira virulence remain mostly unknown. Recently, it has been demonstrated that L. interrogans ClpB (ClpBLi) is essential for bacterial survival under stressful conditions and also during infection. The aim of this study was to provide further insight into the role of ClpB in L. interrogans and answer the question whether ClpBLi as a potential virulence factor may be a target of the humoral immune response during leptospiral infections in mammals.
  
  
  
  ClpBLi consists of 860 amino acid residues with a predicted molecular mass of 96.3 kDa and shows multi-domain organization similar to that of the well-characterized ClpB from Escherichia coli. The amino acid sequence identity between ClpBLi and E. coli ClpB is 52 %. The coding sequence of the clpB Li gene was cloned and expressed in E. coli BL21(DE3) strain. Immunoreactivity of the recombinant ClpBLi protein was assessed with the sera collected from Leptospira-infected animals and uninfected healthy controls. Western blotting and ELISA analysis demonstrated that ClpBLi activates the host immune system, as evidenced by an increased level of antibodies against ClpBLi in the sera from infected animals, as compared to the control group. Additionally, ClpBLi was found in kidney tissues of Leptospira-infected hamsters.
  
  
  
  ClpBLi is both synthesized and immunogenic during the infectious process, further supporting its involvement in the pathogenicity of Leptospira. In addition, the immunological properties of ClpBLi point to its potential value as a diagnostic antigen for the detection of leptospirosis.
authors.affiliation: Department of General and Medical Biochemistry, University of Gdansk, Faculty of Biology, 80-308, Gdańsk, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Krajewska
authors.affiliation: University Centre of Veterinary Medicine JU-UAK, University of Agriculture in Krakow, 30-059, Krakow, Poland.
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Arent
authors.affiliation: Department of General and Medical Biochemistry, University of Gdansk, Faculty of Biology, 80-308, Gdańsk, Poland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Więckowski
authors.affiliation: Departament of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, KS, 66506, USA.
authors.forename: Michal
authors.initials: M
authors.lastname: Zolkiewski
authors.affiliation: Department of General and Medical Biochemistry, University of Gdansk, Faculty of Biology, 80-308, Gdańsk, Poland. sabina.kedzierska-mieszkowska@biol.ug.edu.pl.
authors.forename: Sabina
authors.initials: S
authors.lastname: Kędzierska-Mieszkowska
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D003001:Cloning, Molecular; D006224:Cricetinae; D004195:Disease Models, Animal; D049071:Endopeptidase Clp; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics / Q000276:immunology; D015964:Gene Expression Regulation, Bacterial; D006360:Heat-Shock Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D056724:Immunity, Humoral; D007668:Kidney / Q000033:anatomy & histology / Q000473:pathology; D007921:Leptospira interrogans / Q000235:genetics / Q000276:immunology*; D007922:Leptospirosis / Q000097:blood / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D018832:Molecular Chaperones / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D020539:Sequence Analysis, Protein; D037521:Virulence Factors / Q000235:genetics / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D011994:Recombinant Proteins; D037521:Virulence Factors; D049071:Endopeptidase Clp; C069775:ClpB protein, E coli
keywords: ClpB; Leptospira interrogans; Leptospirosis; Molecular chaperone; Pathogen