title: Porphyromonas gingivalis and related bacteria: from colonial pigmentation to the type IX secretion system and gliding motility.
abstract: Porphyromonas gingivalis is a gram-negative, non-motile, anaerobic bacterium implicated as a major pathogen in periodontal disease. P. gingivalis grows as black-pigmented colonies on blood agar, and many bacteriologists have shown interest in this property. Studies of colonial pigmentation have revealed a number of important findings, including an association with the highly active extracellular and surface proteinases called gingipains that are found in P. gingivalis. The Por secretion system, a novel type IX secretion system (T9SS), has been implicated in gingipain secretion in studies using non-pigmented mutants. In addition, many potent virulence proteins, including the metallocarboxypeptidase CPG70, 35 kDa hemin-binding protein HBP35, peptidylarginine deiminase PAD and Lys-specific serine endopeptidase PepK, are secreted through the T9SS. These findings have not been limited to P. gingivalis but have been extended to other bacteria belonging to the phylum Bacteroidetes. Many Bacteroidetes species possess the T9SS, which is associated with gliding motility for some of these bacteria.
authors.affiliation: Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nakayama
mesh_terms: D018829:Adhesins, Bacterial; D002268:Carboxypeptidases / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D000080867:Gingipain Cysteine Endopeptidases; D000081062:Heme-Binding Proteins; D006420:Hemeproteins / Q000378:metabolism; D006801:Humans; D006867:Hydrolases / Q000378:metabolism; D010858:Pigmentation / Q000502:physiology*; D018272:Porins / Q000502:physiology*; D016966:Porphyromonas gingivalis / Q000502:physiology*; D000076342:Protein-Arginine Deiminases; D012697:Serine Endopeptidases / Q000378:metabolism; D037521:Virulence Factors / Q000502:physiology
chemical_list: D018829:Adhesins, Bacterial; D002352:Carrier Proteins; D000080867:Gingipain Cysteine Endopeptidases; D000081062:Heme-Binding Proteins; D006420:Hemeproteins; D018272:Porins; D037521:Virulence Factors; D006867:Hydrolases; D002268:Carboxypeptidases; D012697:Serine Endopeptidases; D003546:Cysteine Endopeptidases; D000076342:Protein-Arginine Deiminases
keywords: Porphyromonas gingivalis; gliding motility; protease; protein secretion system; review; virulence factors