Helicobacter acinonychis: Genetic and Rodent Infection Studies of a Helicobacter pylori-Like Gastric Pathogen of Cheetahs and Other Big Cats (original) (raw)

Insights into bacterium-host interactions and genome evolution can emerge from comparisons among related species. Here we studied Helicobacter acinonychis (formerly H. acinonyx), a species closely related to the human gastric pathogen Helicobacter pylori. Two groups of strains were identified by randomly amplified polymorphic DNA fingerprinting and gene sequencing: one group from six cheetahs in a U.S. zoo and two lions in a European circus, and the other group from a tiger and a lion-tiger hybrid in the same circus. PCR and DNA sequencing showed that each strain lacked the cag pathogenicity island and contained a degenerate vacuolating cytotoxin (vacA) gene. Analyses of nine other genes (glmM, recA, hp519, glr, cysS, ppa, flaB, flaA, and atpA) revealed a ϳ2% base substitution difference, on average, between the two H. acinonychis groups and a ϳ8% difference between these genes and their homologs in H. pylori reference strains such as 26695.