Comment : Also see description of Sarcina littoralis Poulsen. Source: Isolated from reddened, salted codfish and herring and from Dead Sea water. Habitat: Found in sea-water brine, sea salt and salt lakes; also found to be asso- ciated with a red discoloration of salted fish.
15. Micrococcus denitrificans Beije- rinck, 1910, emend. Sijderius, 1946. (Beije- rinck, Cent. f. Bakt., II Abt., 25, 1910, 53; also see Elema, De bepaling van de oxydatie reductie potentiaal in bacterien cultures en hare betekenis voor de stofwisseling. Thesis, Delft, 1932; Sijderius, Heterotrophe bac- terien die thiosulfaat oxyderon. Thesis, Amsterdam, 1946.) de.ui.tri'fi.cans. L. prep, de away from; L. noun nitrum soda; M.L. noun nitriim nitrate, niter; M.L. v. denitrifico to denitriiy ; M.L. part. adj. denitrificans denitrifying. Description prepared by Dr. W. Ver- hoeven, Delft, Holland. Non-motile coccus, 1 micron in diameter. Some spindle-shaped, even rod-like forms may be observed in young cultures. In old cultures the typical coccus form is pre- dominant. Sometimes aggregates are ob- served. Gram-negative. Grows readilj' on peptone media. Rather salt resistant; develops in media containing no salt to 6 per cent salt. Gelatin stab: No liquefaction. Agar colonies: Circular, entire, smooth, glistening, white, opaque. Broth: Turbid, no pellicle. Milk: Unchanged. Indole not produced. Hydrogen sulfide not produced. No acid or gas produced from glucose. Nitrates and nitrites are hydrogen ac- ceptors in dissimilation, being reduced to nitrous oxide and nitrogen. Ammonia is not produced. Urease activity negative. Catalase-positive. Aerobic. Temperature range, 5° to 37° C. Opti- mum, between 25° and 30° C. In denitrification, ethanol, propanol, glycerol, mannitol, glucose, formate, ace- tate, lactate, succinate, fumarate, citrate, valerionate or asparagine are suitable hy- drogen donators. Grows under autotrophic conditions on thiosulfates as oxidation substrates with the formation of sulfates and sulfuric acid. Sijderius (op. cit., 1946) suggests that Thiobacillus novellvs Starkey is the same as Micrococcus denitrificans Beijerinck. Grows readily under autotrophic condi- tions in a hydrogen atmosphere. Also pro- duces good growth on a mineral medium with nitrate in a hydrogen atmosphere, if certain growth factors are added to the medium. The relationship of Micrococcus denitrifi- cans to Micrococcus halodenitrificans Robin- son and Gibbons (Can. Jour. Botany, 30, 1952, 147) has not been determined. Pre- sumably the latter organism is an obligate, halophilic adaptate of Micrococc^is denitri- ficans (Verhoeven, Koster and van Nievelt, Jour. Microbiol, and Serology, 20, 1954, 279). Source: Isolated from nitrate media ino- culated with soil. Habitat: Presumably widely distributed in soil.
16. Micrococcus halodenitrificans Rob- inson and Gibbons, 1952. (Robinson and Gibbons, Can. Jour. Botany, SO, 1952, 147; also see Robinson, ibid., 30, 1952, 155, and Robinson, Gibbons and Thatcher, Jour. Bact., 64, 1952, 69.) ha.lo.de.ni.tri'fi.cans. Gr. noun hals, halis salt; L. prep de away from; L. noun nitrum soda; M.L. noun nitrum nitrate, niter; M.L. v. denitrifico to denitrify; M.L. part. adj. halodenitrificans salt denitrifying. Description prepared by Dr. N. E. Gib- bons, Ottawa, Canada. Spherical cells 0.5 micron in diameter. Occur singly or in pairs. Salt concentration has little effect on morphology. Gram-nega- tive. Does not grow on media containing less than four per cent salt. Grows readily in peptone media. Gelatin stab: Liquefied. Agar colonies: Circular, entire, convex, l)utyrous, glistening, opaque, cream- colored. Broth: Turbid, no pellicle.
