title: Genome sequence of the pathogenic intestinal spirochete brachyspira hyodysenteriae reveals adaptations to its lifestyle in the porcine large intestine.
abstract: Brachyspira hyodysenteriae is an anaerobic intestinal spirochete that colonizes the large intestine of pigs and causes swine dysentery, a disease of significant economic importance. The genome sequence of B. hyodysenteriae strain WA1 was determined, making it the first representative of the genus Brachyspira to be sequenced, and the seventeenth spirochete genome to be reported. The genome consisted of a circular 3,000,694 base pair (bp) chromosome, and a 35,940 bp circular plasmid that has not previously been described. The spirochete had 2,122 protein-coding sequences. Of the predicted proteins, more had similarities to proteins of the enteric Escherichia coli and Clostridium species than they did to proteins of other spirochetes. Many of these genes were associated with transport and metabolism, and they may have been gradually acquired through horizontal gene transfer in the environment of the large intestine. A reconstruction of central metabolic pathways identified a complete set of coding sequences for glycolysis, gluconeogenesis, a non-oxidative pentose phosphate pathway, nucleotide metabolism, lipooligosaccharide biosynthesis, and a respiratory electron transport chain. A notable finding was the presence on the plasmid of the genes involved in rhamnose biosynthesis. Potential virulence genes included those for 15 proteases and six hemolysins. Other adaptations to an enteric lifestyle included the presence of large numbers of genes associated with chemotaxis and motility. B. hyodysenteriae has diverged from other spirochetes in the process of accommodating to its habitat in the porcine large intestine.
authors.affiliation: Centre for Comparative Genomics, Murdoch University, Murdoch, Western Australia, Australia.
authors.forename: Matthew I
authors.initials: MI
authors.lastname: Bellgard
authors.forename: Phatthanaphong
authors.initials: P
authors.lastname: Wanchanthuek
authors.forename: Tom
authors.initials: T
authors.lastname: La
authors.forename: Karon
authors.initials: K
authors.lastname: Ryan
authors.forename: Paula
authors.initials: P
authors.lastname: Moolhuijzen
authors.forename: Zayed
authors.initials: Z
authors.lastname: Albertyn
authors.forename: Babak
authors.initials: B
authors.lastname: Shaban
authors.forename: Yair
authors.initials: Y
authors.lastname: Motro
authors.forename: David S
authors.initials: DS
authors.lastname: Dunn
authors.forename: David
authors.initials: D
authors.lastname: Schibeci
authors.forename: Adam
authors.initials: A
authors.lastname: Hunter
authors.forename: Roberto
authors.initials: R
authors.lastname: Barrero
authors.forename: Nyree D
authors.initials: ND
authors.lastname: Phillips
authors.forename: David J
authors.initials: DJ
authors.lastname: Hampson
mesh_terms: D000818:Animals; D001483:Base Sequence; D017401:Brachyspira hyodysenteriae / Q000235:genetics*; D016680:Genome, Bacterial / Q000235:genetics*; D007420:Intestine, Large / Q000382:microbiology*; D053858:Metabolic Networks and Pathways; D013552:Swine; D014774:Virulence / Q000235:genetics