title: Construction and characterization of a nonpigmented mutant of Porphyromonas gingivalis: cell surface polysaccharide as an anchorage for gingipains.
abstract: A nonpigmented mutant of Porphyromonas gingivalis was constructed by using transposon mutagenesis. The mutant possessed the transposon DNA at the novel gene porR. Gene targeted mutagenesis revealed that porR was responsible for pigmentation. The porR gene shared similarities with genes of the degT family, the products of which are now considered to be transaminases involved in biosynthesis of sugar portions of cell-surface polysaccharides and aminoglycosides. The porR mutant showed a pleiotropic phenotype: delayed maturation of fimbrillin, preferential presence of Rgp and Kgp proteinases in culture supernatants, and no haemagglutination. The porR mutant had altered phenol extractable polysaccharide compared to the porR(+) sibling strain. A mAb, 1B5, that reacts with sugar portions of P. gingivalis cell surface polysaccharide and membrane-type Rgp proteinase showed no reaction with the cell lysates of the porR mutant. These results indicate that porR is involved in biosynthesis of cell surface polysaccharide that may function as an anchorage for Rgp, Kgp, haemagglutinins and the haemoglobin receptor protein.
authors.affiliation: Departments of Oral Infectious Diseases and Immunology1, Endodontology and Operative Dentistry2 and Pharmacology3, Faculty of Dental Science, Kyushu University, Fukuoka812-8582, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Shoji
authors.affiliation: Departments of Oral Infectious Diseases and Immunology1, Endodontology and Operative Dentistry2 and Pharmacology3, Faculty of Dental Science, Kyushu University, Fukuoka812-8582, Japan.
authors.forename: Dinath B
authors.initials: DB
authors.lastname: Ratnayake
authors.affiliation: Departments of Oral Infectious Diseases and Immunology1, Endodontology and Operative Dentistry2 and Pharmacology3, Faculty of Dental Science, Kyushu University, Fukuoka812-8582, Japan.
authors.forename: Yixin
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Departments of Oral Infectious Diseases and Immunology1, Endodontology and Operative Dentistry2 and Pharmacology3, Faculty of Dental Science, Kyushu University, Fukuoka812-8582, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Kadowaki
authors.affiliation: Departments of Oral Infectious Diseases and Immunology1, Endodontology and Operative Dentistry2 and Pharmacology3, Faculty of Dental Science, Kyushu University, Fukuoka812-8582, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Microbiology, School of Dentistry, Aichi-Gakuin University, Nagoya464-8650, Japan4.
authors.forename: Fuminobu
authors.initials: F
authors.lastname: Yoshimura
authors.affiliation: Departments of Oral Infectious Diseases and Immunology1, Endodontology and Operative Dentistry2 and Pharmacology3, Faculty of Dental Science, Kyushu University, Fukuoka812-8582, Japan.
authors.forename: Akifumi
authors.initials: A
authors.lastname: Akamine
authors.affiliation: Department of Medical Microbiology, Division of Molecular Pathology Infection and Immunity, St Bartholomew's and the Royal London School of Medicine and Dentistry, London E1 2AA, UK5.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Curtis
authors.affiliation: Department of Microbiology, School of Dentistry, Nagasaki University, Nagasaki 852-8588, Japan6.
authors.forename: Koji
authors.initials: K
authors.lastname: Nakayama
mesh_terms: D018829:Adhesins, Bacterial / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites; D002876:Chromosomes, Bacterial / Q000235:genetics; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D000080867:Gingipain Cysteine Endopeptidases; D006386:Hemagglutination Tests; D006388:Hemagglutinins / Q000378:metabolism*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016254:Mutagenesis, Insertional; D010641:Phenotype; D010858:Pigmentation / Q000235:genetics; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D016966:Porphyromonas gingivalis / Q000235:genetics* / Q000472:pathogenicity; D015183:Restriction Mapping; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D000637:Transaminases / Q000737:chemistry / Q000235:genetics*
chemical_list: D018829:Adhesins, Bacterial; D000080867:Gingipain Cysteine Endopeptidases; D006388:Hemagglutinins; D011135:Polysaccharides, Bacterial; D000637:Transaminases; D003546:Cysteine Endopeptidases