janthinobacterium janthinobacterium janthinobacterium is a genus of gram-negative soil bacteria. the name is from latin janthinus, which means "violet" or "violet-blue". it produces a purple-violet pigment, manifests diverse energy metabolism abilities, and tolerates cold, ultraviolet radiation, and other environmental stressors. janthinobacterium scientific classification domain: bacteria phylum: pseudomonadota class: betaproteobacteria order: burkholderiales family: oxalobacteraceae genus: janthinobacteriumde ley et al. 1978 (approved lists 1980) emend. lincoln et al. 1999 type species janthinobacterium lividum species j. agaricidamnosum j. aquaticum j. lividum j. psychrotolerans j. rivuli j. svalbardensis j. violaceinigrum