title: Molecular cloning and expression of a major surface protein (the 75-kDa protein) of Porphyromonas (Bacteroides) gingivalis in Escherichia coli.
abstract: A major immunodominant surface protein (the 75-kDa protein) of Porphyromonas (Bacteroides) gingivalis 381 has been purified and its amino-terminal amino acid sequence has been determined. Using oligonucleotide probes corresponding to the sequence, we identified a recombinant plasmid clone carrying a single 4.2-kb BamHI fragment from pUC19 libraries of P. gingivalis. The BamHI fragment transferred to the bacteriophage T7 RNA polymerase/promoter expression vector system produced a slightly larger (77-kDa) protein, a precursor form, immunoreactive to the antibody against the 75-kDa protein, suggesting that the cloned DNA fragment probably carried an entire gene for the 75-kDa protein. Genomic Southern analysis revealed a single copy of the 75-kDa protein gene per genome among all P. gingivalis strains tested, and that no homologous genes are present in other black-pigmented Bacteroides species. These observations suggest that the 75-kDa protein gene may be useful as a specific DNA probe to classify or to detect this organism.
authors.affiliation: Department of Periodontology, School of Dentistry, Hokkaido University, Sapporo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.forename: T
authors.initials: T
authors.lastname: Takasawa
authors.forename: F
authors.initials: F
authors.lastname: Yoshimura
authors.forename: M
authors.initials: M
authors.lastname: Ozeki
authors.forename: M
authors.initials: M
authors.lastname: Kawanami
authors.forename: H
authors.initials: H
authors.lastname: Kato
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D016056:Immunodominant Epitopes / Q000235:genetics / Q000276:immunology; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D016966:Porphyromonas gingivalis / Q000145:classification / Q000235:genetics* / Q000276:immunology; D015183:Restriction Mapping
chemical_list: D001426:Bacterial Proteins; D016056:Immunodominant Epitopes; D008565:Membrane Proteins; D015345:Oligonucleotide Probes; C075509:major surface protein, Porphyromonas gingivalis