chromobacterium chromobacterium chromobacterium is a genus of gram-negative rod-shaped bacteria.: 279 currently, eleven species within the genus are known, two of those are chromobacterium violaceum and chromobacterium subtsugae; the latter was discovered by scientists at the agricultural research service in beltsville, maryland. chromobacterium blood agar plate culture of chromobacterium violaceum. scientific classification domain: bacteria phylum: pseudomonadota class: betaproteobacteria order: neisseriales family: neisseriaceae genus: chromobacteriumbergonzini 1880 type species chromobacterium violaceum species c. alkanivorans c. amazonense c. aquaticum c. haemolyticum c. phragmitis c. piscinae c. pseudoviolaceum c. rhizoryzae c. subtsugae c. vaccinii c. violaceum