title: Antigenic characterization of dimorphic surface protein in Mycobacterium tuberculosis.
abstract: The Mycobacterium tuberculosis Rv0679c protein is a surface protein that contributes to host cell invasion. We previously showed that a single nucleotide transition of the Rv0679c gene leads to a single amino acid substitution from asparagine to lysine at codon 142 in the Beijing genotype family. In this study, we examined the immunological effect of this substitution. Several recombinant proteins were expressed in Escherichia coli and Mycobacterium smegmatis and characterized with antisera and two monoclonal antibodies named 5D4-C2 and 8G10-H2. A significant reduction of antibody binding was detected by enzyme-linked immunosorbent assay (ELISA) and western blot analysis in the Lys142-type protein. This reduction of 8G10-H2 binding was more significant, with the disappearance of a signal in the proteins expressed by recombinant mycobacteria in western blot analysis. In addition, epitope mapping analysis of the recombinant proteins showed a linear epitope by 5D4-C2 and a discontinuous epitope by 8G10-H2. The antibody recognizing the conformational epitope detected only mycobacterial Asn142-type recombinant protein. Our results suggest that a single amino acid substitution of Rv0679c has potency for antigenic change in Beijing genotype strains.
authors.affiliation: Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, 86 Nishi-cho, Yonago, Tottori 683-8503, Japan matsubat@med.tottori-u.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuba
authors.affiliation: Department of Emerging Infectious Diseases, Graduate School of Medicine, Tohoku University 1-1 Seiryo-cho, Aoba-ku, Sendai 980-8574, Japan.
authors.forename: Umme Ruman
authors.initials: UR
authors.lastname: Siddiqi
authors.affiliation: Department of Emerging Infectious Diseases, Graduate School of Medicine, Tohoku University 1-1 Seiryo-cho, Aoba-ku, Sendai 980-8574, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Hattori
authors.affiliation: Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Kita 20-Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan The Global Station for Zoonosis Control, Hokkaido University Global Institution for Collaborative Research and Education, Kita 20-Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan.
authors.forename: Chie
authors.initials: C
authors.lastname: Nakajima
authors.affiliation: Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, 86 Nishi-cho, Yonago, Tottori 683-8503, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Fujii
authors.affiliation: Division of Bioresources, Hokkaido University Research Center for Zoonosis Control, Kita 20-Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan The Global Station for Zoonosis Control, Hokkaido University Global Institution for Collaborative Research and Education, Kita 20-Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0020, Japan.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Suzuki
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000302:isolation & purification; D000942:Antigens, Bacterial / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D001666:Binding Sites, Antibody; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D004926:Escherichia coli / Q000235:genetics; D051379:Mice; D020102:Mycobacterium smegmatis / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000737:chemistry* / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D000939:Epitopes; D011994:Recombinant Proteins
keywords: Beijing genotype; Ddimorphism; epitope; mycobacteria; tuberculosis