Photobacterium

A genus of motile and nonmotile, aerobic to facultatively anaerobic bacteria (family Pseudomonadaceae) containing Gram-negative coccobacilli and occasional rods; under adverse conditions pleomorphic forms frequently occur. Motile cells have polar flagella. The metabolism of these organisms is fermentative. They are usually luminescent and occur symbiotically in tissues of luminous organs of cephalopods and deep-sea fishes and on the skin and in the intestines of some marine fish. The type species is P. phosphoreum.

- P. phosphoreum a luminescent species found on dead fish and in sea water; it is the type species of the genus P..

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Pho·to·bac·te·ri·um (fo″to-bak-tērґe-əm) [photo- + bacterium] a genus of halophilic, gram-negative marine bacteria of the family Vibrionaceae, consisting of plump, straight rods that are motile by means of polar flagella; organisms are facultatively anaerobic and chemo-organotrophic, and some are luminescent. The type species is P. phosphoreum.