title: Comparative Genomics of the Genus Porphyromonas Identifies Adaptations for Heme Synthesis within the Prevalent Canine Oral Species Porphyromonas cangingivalis.
abstract: Porphyromonads play an important role in human periodontal disease and recently have been shown to be highly prevalent in canine mouths. Porphyromonas cangingivalis is the most prevalent canine oral bacterial species in both plaque from healthy gingiva and plaque from dogs with early periodontitis. The ability of P. cangingivalis to flourish in the different environmental conditions characterized by these two states suggests a degree of metabolic flexibility. To characterize the genes responsible for this, the genomes of 32 isolates (including 18 newly sequenced and assembled) from 18 Porphyromonad species from dogs, humans, and other mammals were compared. Phylogenetic trees inferred using core genes largely matched previous findings; however, comparative genomic analysis identified several genes and pathways relating to heme synthesis that were present in P. cangingivalis but not in other Porphyromonads. Porphyromonas cangingivalis has a complete protoporphyrin IX synthesis pathway potentially allowing it to synthesize its own heme unlike pathogenic Porphyromonads such as Porphyromonas gingivalis that acquire heme predominantly from blood. Other pathway differences such as the ability to synthesize siroheme and vitamin B12 point to enhanced metabolic flexibility for P. cangingivalis, which may underlie its prevalence in the canine oral cavity.
authors.affiliation: The WALTHAM Centre for Pet Nutrition, Waltham-on-the-Wolds, United Kingdom ciaran.oflynn@effem.com.
authors.forename: Ciaran
authors.initials: C
authors.lastname: O'Flynn
authors.affiliation: The WALTHAM Centre for Pet Nutrition, Waltham-on-the-Wolds, United Kingdom.
authors.forename: Oliver
authors.initials: O
authors.lastname: Deusch
authors.affiliation: The ithree Institute, University of Technology Sydney, Ultimo, New South Wales, Australia.
authors.forename: Aaron E
authors.initials: AE
authors.lastname: Darling
authors.affiliation: Department of Evolution and Ecology, University of California, Davis Department of Medical Microbiology and Immunology, University of California, Davis UC Davis Genome Center, University of California, Davis.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Eisen
authors.affiliation: The WALTHAM Centre for Pet Nutrition, Waltham-on-the-Wolds, United Kingdom.
authors.forename: Corrin
authors.initials: C
authors.lastname: Wallis
authors.affiliation: The WALTHAM Centre for Pet Nutrition, Waltham-on-the-Wolds, United Kingdom.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Davis
authors.affiliation: The WALTHAM Centre for Pet Nutrition, Waltham-on-the-Wolds, United Kingdom.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Harris
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000818:Animals; D004285:Dogs; D016680:Genome, Bacterial; D006418:Heme / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D006801:Humans; D009055:Mouth / Q000378:metabolism / Q000382:microbiology; D010802:Phylogeny; D016966:Porphyromonas gingivalis / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity
chemical_list: D006418:Heme
keywords: Porphyromonas; canine; comparative genomics; periodontal disease; plaque