aquabacter aquabacter aquabacter is an oxidase and catalase-positive genus of bacteria from the family of hyphomicrobiaceae. it contains only the single species a. spiritensis. aquabacter scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: hyphomicrobiales family: xanthobacteraceae genus: aquabacterirgens et al. 1993 type species aquabacter spiritensis species a. spiritensis