bartonella chomelii bartonella chomelii bartonella chomelii is a gram-negative, oxidase- and catalase-negative bacteria from the genus bartonella with a unipolar flagellum which was isolated from a domestic cattle (bos taurus). bartonella chomelii is named after bruno b. chomel. bartonella chomelii scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: hyphomicrobiales family: bartonellaceae genus: bartonella species: b. chomelii binomial name bartonella chomeliimaillard et al. 2004