bartonella australis bartonella australis bartonella australis is a gram-negative bacterium of the genus bartonella which was isolated from eastern grey kangaroos (macropus giganteus). bartonella australis scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: hyphomicrobiales family: bartonellaceae genus: bartonella species: b. australis binomial name bartonella australisfournier et al. 2007