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Brachyspira
About: Brachyspira is a research topic. Over the lifetime, 265 publications have been published within this topic receiving 6081 citations.
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TL;DR: The ultrastructure of spirochetes obtained from rectal biopsies of patients with intestinal spirochetosis was studied by means of negative staining and ultrathin sectioning and it is proposed that the present strains constitute a new genus, Brachyspira, of the family Treponemataceae.
Abstract: The ultrastructure of spirochetes obtained from rectal biopsies of patients with intestinal spirochetosis was studied by means of negative staining and ultrathin sectioning. The cells were sigmoidal with tapered ends, 2 to 6 microns long, with a wavelength of 2 microns. Four flagella were inserted at each end of the cells. The maximal cell width was about 0.2 microns. The spirochetes were cultured on tryptose soy blood agar plates. They were anaerobic and grew, although very slowly, at 37 to 38.5 degrees C in an atmosphere of 5% CO2-95% H2. Two types of colonies could be distinguished. The growth characteristics and the morphology of the isolated spirochetes differ from those of previously isolated spirochetal strains. Consequently, it is proposed that the present strains constitute a new genus, Brachyspira, of the family Treponemataceae. The type species is Brachyspira aalborgi, the type strain of which is 513A (NCTC 11492).
207 citations
TL;DR: A combined evaluation of the phenotypical properties of five Serpulina type or reference strains and 163 Swedish isolates of spirochaetes from pigs and two from birds was made, finding that there was a statistical relationship between pigs with diarrhoea and the isolation of group IV spirochametes but no relationship with group III spiroCHAetes.
141 citations
TL;DR: It is proposed to transfer the three species of the genus Serpulina to the genus Brachyspira, because their 16S ribosomal DNA sequences were related more than 96.0%.
Abstract: The phylogenetic positions of Serpulina hyodysenteriae, Serpulina innocens, Serpulina pilosicoli and Brachyspira aalborgi were studied. Complete 16S ribosomal DNA sequences of these three species and B. aalborgi revealed that their 16S rDNA sequences were related more than 96.0%. The mol% guanine plus cytosine (G + C) of B. aalborgi DNA was 27.1, and was similar to those of the 3 members of the genus Serpulina. The homologous rates using 32P-labeled B. aalborgi chromosome DNA in DNA-DNA reassociation tests were 22.0% to S. hyodysenteriae, 19.1% to S. innocens and 17.2% to S. pilosicoli. Therefore, we propose to transfer the three species of the genus Serpulina to the genus Brachyspira. Descriptions of Brachyspira hyodysenteriae comb. nov., Brachyspira innocens comb. nov. and Brachyspira pilosicoli comb. nov., and an emended description of B. aalborgi are given. Phenotypic characteristics of the 4 members of the genus Brachyspira were also studied. They fermented fructose, galactose, glucose, lactose, maltose, man-nose, raffinose and trehalose; however, B. aalborgi did not ferment raffinose. All of them hydrolyzed esculin but did not produce indole except for B. hyodysenteriae. The protein profile of B. aalborgi was different from those of the four strains of B. hyodysenteriae, B. innocens and B. pilosicoli, but the heavy bands with molecular sizes of 49.4 and 52.3 kDa of B. aalborgi were quite similar to those of B. innocens in the points of quantity and molecular size. In immunoblotting tests, B. aalborgi reacted well with anti-B. innocens and B. pilosicoli sera, but reacted weakly with anti-B. hyodysenteriae serum. Only one heavy band and several faint bands were revealed by the reaction between B. aalborgi and anti-B. hyodysenteriae serum, and the heavy band was common among these strains.
124 citations
TL;DR: Genetic relationships were assessed amongst 175 isolates of anaerobic intestinal spirochaetes, including 72 isolates from individuals living in different parts of the world, 102 from pigs and one from a dog, and amongst porcine isolates belonging to the genus Serpulina, a possible new species was identified.
Abstract: Summary
Multilocus enzyme electrophoresis was used to assess genetic relationships amongst 175 isolates of anaerobic intestinal spirochaetes, including 72 isolates from individuals living in different parts of the world, 102 from pigs and one from a dog. Amongst porcine isolates belonging to the genus Serpulina, a possible new species was identified. All but one of the isolates from man were clustered with the canine isolate and 59 porcine isolates in a distinct group that we have previously called “Anguillina coli”. The human and animal spirochaetes in this group had four-to-six axial flagella and most were recovered from individuals with diarrhoea. They included a strain of the so-called “Serpulina jonesii”, that was not a true serpulina. These 71 human isolates were distributed into 44 electrophoretic types and had a mean genetic diversity of 0·32. These were further divided into 26 clonal groups. Three of these clones also contained porcine isolates, one of which was strain P43/6/78, the agent of porcine intestinal spirochaetosis. Four of the clones contained human isolates from different sources. One included isolates from Western Australian Aboriginal children and from Italian adults, and the other three contained isolates from Western Australian Aboriginal children and from homosexual males in Sydney, New South Wales. There were no known connections between these human populations. The other spirochaete of human origin was Brachyspira aalborgi, which was distinct from isolates in the genera Serpulina and “Anguillina”. Both B. aalborgi and “A. coli” have been associated with human cases of intestinal spirochaetosis. Others have questioned the clinical significance of colonisation by B. aalborgi, but we suggest that isolates of “A. coli” may be the cause of some clinical cases of intestinal spirochaetosis.
122 citations
TL;DR: 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.
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.
119 citations