An aerobic, oxidase-positive, gram-negative, bacillus that grows well on nonselective media. Some members produce a blue-green or yellow-green fluorescent pigment, others produce a brown-yellow, red-tan, pink, or yellow pigment. It is ubiquitous in nature and has been isolated environmentally from fruits, vegetables, ornamental plants, solutions, body lotions, faucets, sinks, soil, sponges, mops and water. Some members are plant pathogens while some are human and animal pathogens. It has been isolated from the respiratory tract, burns, wounds, blood, urogenital tract, spinal and joint fluid of humans. It is a major cause of nosocomial (hospital-acquired) infections.