methylophilaceae methylophilaceae the methylophilaceae are a family of pseudomonadota, given their own order. like all pseudomonadota, they are gram-negative. the cells are slightly curved or straight rod-shaped. methylophilaceae scientific classification domain: bacteria phylum: pseudomonadota class: betaproteobacteria order: methylophilaceaegarrity et al. 2006 genera methylophilus methylobacillus methylovorax