Brachyspira hyodysenteriae WA1

Brachyspira hyodysenteriae is an anaerobic spirochete that is the causative agent of swine dysentery, severe inflammation of the large intestine with a bloody mucous diarrhea of pigs. The bacterium can survive for several weeks in cold moist conditions but not under warm dry conditions. It spreads slowly, building up in numbers as the dose rate of the causal agent builds up in the environment. Pigs that recover develop a low immunity and rarely suffer from the disease again. It can be spread by other organisms (flies, mice, birds and dogs) or external mechanical factors; its main habitat is the porcine cecum and colon. It is chemotactically attracted to mucin which it penetrates with a corkscrew-like motility. Many of the predicted CDS show a higher match to Escherichia (36%) and Clostridium (15%) than to other spirochete CDS (only 5%), and it is thought that their genes were probably acquired via horizontal gene transfer. About half of these Escherichia and Clostridium-like CDS are involved in metabolism, suggesting they enhance survival in the large intestine. It also has 123 predicted transport CDS, pathways for glycolysis, gluconeogenesis, a non-oxidative pentose phosphate pathway, nucleotide metabolism, lipopolysaccharide biosynthesis and a respiratory electron transport chain. ATP is probably generated by sugar metabolism. It has 314 putative virulence factors, including proteases, hemolysins, ankyrin proteins, potential type III secretion system and CDS involved in chemotaxis (adapted from http://www.thepigsite.com/diseaseinfo/116/swine-dysentery and PubMed 19262690). (HAMAP: BRAHW)