title: Lack of a surface layer in Tannerella forsythia mutants deficient in the type IX secretion system.
abstract: Tannerella forsythia, a Gram-negative anaerobic bacterium, is an important pathogen in periodontal disease. This bacterium possesses genes encoding all known components of the type IX secretion system (T9SS). T. forsythia mutants deficient in genes orthologous to the T9SS-encoding genes porK, porT and sov were constructed. All porK, porT and sov single mutants lacked the surface layer (S-layer) and expressed less-glycosylated versions of the S-layer glycoproteins TfsA and TfsB. In addition, these mutants exhibited decreased haemagglutination and increased biofilm formation. Comparison of the proteins secreted by the porK and WT strains revealed that the secretion of several proteins containing C-terminal domain (CTD)-like sequences is dependent on the porK gene. These results indicate that the T9SS is functional in T. forsythia and contributes to the translocation of CTD proteins to the cell surface or into the extracellular milieu.
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Narita
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Sato
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Hideharu
authors.initials: H
authors.lastname: Yukitake
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Shoji
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Nakane
authors.affiliation: Department of Microbiology, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Nagano
authors.affiliation: Department of Microbiology, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.
authors.forename: Fuminobu
authors.initials: F
authors.lastname: Yoshimura
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Naito
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 819-8588, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Nakayama
mesh_terms: D058947:Bacterial Secretion Systems / Q000235:genetics*; D041963:Bacteroidetes / Q000737:chemistry* / Q000235:genetics* / Q000502:physiology; D008562:Membrane Glycoproteins / Q000032:analysis*; D026901:Membrane Transport Proteins / Q000235:genetics*; D009154:Mutation
chemical_list: D058947:Bacterial Secretion Systems; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; C055764:S-layer proteins