194 



ORDER I. PSEUDOMONADALES 



jerinck, Arch, neerl. d. Sci. exact, et natur., 

 £3, 1889, 401; Photobacter phosphoreum 

 Beijerinck, Folia Microbiologica, Delft, 

 4, 1916, 15; Ford, Textb. of Bact., 1927, 

 615.) 



phos.pho're.um. Gr. v. phosphor eo to 

 bring light; M.L. adj. phosphoreus light- 

 bearing. 



Description taken from Fischer (op. cit., 

 1888, 107) and Beijerinck {op. cit., 1889, 

 401). 



Coccobacilli, 0.5 to 2.0 microns; oc- 

 casional rods are 0.5 to 1.0 micron. In the 

 presence of glucose, especially glucose and 

 asparagine combined, some of the cells tend 

 to branch and to take the form of bac- 

 teroids. Frequently occur as zoogloeae. 

 Non-motile (Fischer); some cells show a 

 sluggish motility (Beijerinck); (Johnson, 

 personal communication, 1953, stated that 

 even electron micrographs failed to reveal 

 flagella) ; actively motile on suitable media 

 (Kluyver, personal communication, June, 

 1953) ; Leifson (personal communication, 

 July, 1953) reports that an occasional cell 

 of culture L342 from Delft shows mono- 

 trichous flagellation. Stain lightly with 

 aniline dyes. Gram-negative (Manual, 3rd 

 ed., 1930, 178). 



Gelatin: No liquefaction. 



Agar slant: Grayish white layer (Manual, 

 loc. cit.). 



Broth: Slightly turbid with thin pellicle 

 (Manual, loc. cit.). 



Potato: Ordinary acid potato, no growth; 

 neutralized with sodium phosphate, thin 

 brownish growth (Chester, Ann. Rept. Del. 

 Col. Agr. Exp. Sta., 9, 1897, 124). 



Proteolytic enzymes not secreted. 



Glucose, fructose, maltose and galactose 

 are anaerobically fermented with the pro- 

 duction of gas. This is a butanediol fermen- 

 tation that produces H2 and CO2 (Kluyver, 

 personal communication, 1953). 



Aerobic, facultatively anaerobic. 



Minimum temperature, between 5° and 

 10° C. 



Quality of luminescence: Bluish green. 



Salt tolerance: To assure phosphorescence 

 and good growth, the osmotic tension of 

 inorganic salt solutions used for cultivation 

 should be equivalent to that produced in a 

 3 per cent sodium chloride solution. 



Distinctive characters: Coccoid bacteria 

 which do not liquefy gelatin and which 

 produce acid and gas from glucose but not 

 from lactose. In the presence of glucose, 

 especially when combined with asparagine, 

 the cells swell up greatly and lose their 

 luminescent property. Luminescence on 

 organic matter occurs only when there is a 

 sufficient proportion of inorganic salt. 



Comments: Several publications which 

 antedate that of Fischer (op. cit., 1888, 107) 

 allude to the fact that the binomial Bac- 

 terium phosphorescens might have been 

 effectively published earlier than 1888. One 

 reference (Anonymous, Nature, 35, 1886- 

 1887, 377) cites Hermes, the Director of the 

 Berlin Aquarium, as having published an 

 article in which he describes and names as 

 Bacteriian phosphorescens a luminescent 

 organism obtained from a specimen of cod 

 (Gadus callarias) at the Berlin Aquarium; 

 this was the same organism which Fischer 

 secured from the Berlin Aquarium and 

 which he named Bacterium phosphorescens. 

 A second reference (Ludwig, Cent. f. Bakt., 

 2, 1887, 404) states that Hermes demon- 

 strated before the Berlin Society the phos- 

 phorescent bacterium from the Berlin 

 Aquarium under the name Bacterium phos- 

 phorescens. Other references (Anonymous, 

 Gesell. deutsch. Naturforsch. u. Aerzte, 

 Tageblatt, 60, 1887, 77 and 254) showed 

 that Hermes used this organism several 

 times for demonstration purposes in the 

 Aquarium and before the Society. As 

 Hermes' publication has not been found, and 

 as the binomial Bacterium phosphorescens is 

 not effectively published in anj- of the three 

 references given directly above, Fischer is 

 credited here as the author of this binomial. 



Considerable confusion exists in the 

 literature concerning this species, most of 

 which can be elucidated by the following: 

 (1) Fischer (Ztschr. f. Hyg., 2, 1887, 54-92) 

 described an organism, isolated from sea 

 water from the West Indies, which he named 

 Bacillus phosphorescens; (2) a second species 

 of phosphorescent bacteria, obtained from 

 the Berlin Aquarium, was described, but 

 not named, by Fischer in a supplement to 

 the work cited above (ibid., 92-95); Leh- 

 mann (Cent. f. Bakt., 5, 1889, 785) also 

 described an organism obtained from the 



