title: The Porphyromonas gingivalis hemagglutinins HagB and HagC are major mediators of adhesion and biofilm formation.
abstract: Porphyromonas gingivalis is a bacterium associated with chronic periodontitis that possesses a family of genes encoding hemagglutinins required for heme acquisition. In this study we generated ΔhagB and ΔhagC mutants in strain W83 and demonstrate that both hagB and hagC are required for adherence to oral epithelial cells. Unexpectedly, a double ΔhagB/ΔhagC mutant had less severe adherence defects than either of the single mutants, but was found to exhibit increased expression of the gingipain-encoding genes rgpA and kgp, suggesting that a ΔhagB/ΔhagC mutant is only viable in populations of cells that exhibit increased expression of genes involved in heme acquisition. Disruption of hagB in the fimbriated strain ATCC33277 demonstrated that HagB is also required for stable attachment of fimbriated bacteria to oral epithelial cells. Mutants of hagC were also found to form defective single and multi-species biofilms that had reduced biomass relative to biofilms formed by the wild-type strain. This study highlights the hitherto unappreciated importance of these genes in oral colonization and biofilm formation.
authors.affiliation: Division of Oral Biosciences, Dublin Dental University Hospital, School of Dental Science, Trinity College Dublin, University of Dublin, Dublin, Ireland.
authors.forename: E
authors.initials: E
authors.lastname: Connolly
authors.affiliation: Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, School of Dental Science, University of Glasgow, Glasgow, UK.
authors.forename: E
authors.initials: E
authors.lastname: Millhouse
authors.affiliation: Division of Oral Biosciences, Dublin Dental University Hospital, School of Dental Science, Trinity College Dublin, University of Dublin, Dublin, Ireland.
authors.forename: R
authors.initials: R
authors.lastname: Doyle
authors.affiliation: Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, School of Dental Science, University of Glasgow, Glasgow, UK.
authors.forename: S
authors.initials: S
authors.lastname: Culshaw
authors.affiliation: Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, School of Dental Science, University of Glasgow, Glasgow, UK.
authors.forename: G
authors.initials: G
authors.lastname: Ramage
authors.affiliation: Division of Oral Biosciences, Dublin Dental University Hospital, School of Dental Science, Trinity College Dublin, University of Dublin, Dublin, Ireland.
authors.forename: G P
authors.identifier: 0000-0003-0469-1788
authors.initials: GP
authors.lastname: Moran
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics / Q000502:physiology*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics* / Q000502:physiology; D018441:Biofilms / Q000254:growth & development*; D045744:Cell Line, Tumor; D003546:Cysteine Endopeptidases / Q000502:physiology; D004847:Epithelial Cells / Q000382:microbiology; D004912:Erythrocytes / Q000382:microbiology; D000080867:Gingipain Cysteine Endopeptidases; D006388:Hemagglutinins / Q000235:genetics / Q000502:physiology; D006790:Host-Parasite Interactions; D006801:Humans; D037102:Lectins / Q000235:genetics / Q000502:physiology; D009055:Mouth / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000235:genetics / Q000502:physiology*; D017384:Sequence Deletion; D012756:Sheep
chemical_list: D018829:Adhesins, Bacterial; D001426:Bacterial Proteins; D000080867:Gingipain Cysteine Endopeptidases; C098582:HagB protein, Porphyromonas gingivalis; C102649:HagC protein, Porphyromonas gingivalis; D006388:Hemagglutinins; D037102:Lectins; D003546:Cysteine Endopeptidases
keywords: 
  Porphyromonas gingivalis
  ; adhesion; biofilm; hemagglutinin