title: Analysis of Multiple Brachyspira hyodysenteriae Genomes Confirms That the Species Is Relatively Conserved but Has Potentially Important Strain Variation.
abstract: The intestinal spirochete Brachyspira hyodysenteriae is an important pathogen in swine, causing mucohemorrhagic colitis in a disease known as swine dysentery. Based on the detection of significant linkage disequilibrium in multilocus sequence data, the species is considered to be clonal. An analysis of the genome sequence of Western Australian B. hyodysenteriae strain WA1 has been published, and in the current study 19 further strains from countries around the world were sequenced with Illumina technology. The genomes were assembled and aligned to over 97.5% of the reference WA1 genome at a percentage sequence identity better than 80%. Strain regions not aligned to the reference ranged between 0.2 and 2.5%. Clustering of the strain genes found on average 2,354 (88%) core genes, 255 (8.6%) ancillary genes and 77 (2.9%) unique genes per strain. Depending on the strain the proportion of genes with 100% sequence identity to WA1 ranged from 85% to 20%. The result is a global comparative genomic analysis of B. hyodysenteriae genomes revealing potential differential phenotypic markers for numerous strains. Despite the differences found, the genomes were less varied than those of the related pathogenic species Brachyspira pilosicoli, and the analysis supports the clonal nature of the species. From this study, a public genome resource has been created that will serve as a repository for further genetic and phenotypic studies of these important porcine bacteria. This is the first intra-species B. hyodysenteriae comparative genomic analysis.
authors.affiliation: Centre for Comparative Genomics, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Black
authors.affiliation: Centre for Comparative Genomics, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Paula
authors.initials: P
authors.lastname: Moolhuijzen
authors.affiliation: Centre for Comparative Genomics, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Roberto
authors.initials: R
authors.lastname: Barrero
authors.affiliation: School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Tom
authors.initials: T
authors.lastname: La
authors.affiliation: School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Nyree
authors.initials: N
authors.lastname: Phillips
authors.affiliation: School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Hampson
authors.affiliation: Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig University Giessen, Giessen, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Herbst
authors.affiliation: Institute for Hygiene and Infectious Diseases of Animals, Justus-Liebig University Giessen, Giessen, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Barth
authors.affiliation: School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Matthew
authors.initials: M
authors.lastname: Bellgard
mesh_terms: D000818:Animals; D017401:Brachyspira hyodysenteriae / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics*; D016680:Genome, Bacterial / Q000235:genetics*; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology; D007422:Intestines / Q000382:microbiology; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017421:Sequence Analysis; D013552:Swine / Q000382:microbiology; D013553:Swine Diseases / Q000382:microbiology