Pleomorphic rods, 1 to 2 microns in length, with rounded ends, occurring singlj^ and in clusters. Intracellular forms are usually encapsulated. Non-motile. Gram-negative. Originally this organism was described as being non-cultivable on ordinary media; lately, however, it has been shown by Dunham and Rake (Amer. Jour. Syphilis, Gonorrhea and Venereal Diseases, 32, 1948, 145) and b}^ Rake and Oskaj^ (Jour. Bact., 55, 1948, 667) that, after adaptation, growth can be effected on artificial media. Chick embryo : Grows readily in yolk sac and feebly in amniotic fluid of developing chick embryo. Embryonic j^olk medium: Growth occurs. Levinthal beef heart infusion agar colo- nies (after adaptation) : At first shiny and translucent, increasing in size until the larger colonies measure 1.5 mm in diam- eter; gradually become gray, later brownish (Rake and Oskay, ibid., 668). Distinctive characters : Encapsulated forms readily demonstrated by means of Wright's stain as blue bacillary bodies sur- rounded by well defined, dense, pinkish capsules. Non-encapsulated forms are vari- able in morphology. Characteristic safety- pin forms may be demonstrated. Not pathogenic for the common experi- mental animals. Source: Isolated from granulomatous lesions of man. Habitat: Human lesions. The cause of granuloma inguinale. Genus VII. Moraxella Lwoff, 1939.* (Z)zp?o6aci7Z?^s McNab, Klinische Monatsbl. f. Augenheilk., 4^, 1904, 65; not Diplobacillus Weichselbaum, Cent. f. Bakt., 2, 1887, 212; Lwoff, Ann. Inst. Past., 62, 1939, 168.) Mo.rax.el'la. M.L. dim. ending -ella; M.L. fem.n. Moraxella named for V. Morax, the bacteriologist who first isolated the type species of this genus. Small, short, rod-shaped cells which occur as diplobacilli and which are sometimes de- scribed as diplococci; occasionally occur singly. Non-motile. Gram-negative. Do not re- quire V (phosphopyridine nucleotide) or X (hemin) factors for growth; growth is, however, dependent upon or improved with the addition of serum or ascitic fluid. Litmus milk is unchanged or becomes alkaline. Carbohydrates generally not attacked. Activelj^ proteo- lytic, liquefying inspissated blood serum and even egg media. Oxidase-positive. Aerobic. Found as parasites and pathogens in warm-blooded animals, being especially found in association with diseases of the eye. The type species is Moraxella lacunata (Eyre) Lwoff. Key to the species of genus Moraxella. I. Does not grow in gelatin. 1. Moraxella lacunata. II. Grow in gelatin. A. Gelatin readily liquefied. No change in litmus milk. 2. Moraxella liguefaciens . B. Gelatin slowly liquefied. Litmus milk becomes alkaline with partial coagulation. 3. Moraxella bovis. 1. Moraxella lacunata (Eyre, 1899) Lwoff, 1939. (Diplobacille de la conjuncti- vite subaigue, Morax, Ann. Inst. Past., 10, 1896, 337; Diplobacillus of chronic conjunc- tivitis, Axenfeld, Cent. f. Bakt., I Abt., 21, 1897, 1; Bacterixnn conjunctivitis Chester, Ann. Rept. Del. Col. Agr. Exp. Sta., 9, 1897, 66; not Bacterium conjunctivitis Chester, ibid., 67; Bacillus lacjinatus Eyre, Jour. Path, and Bact., 6, 1899, 5; not Bacillus lacunatus Wright, Memoirs Nat. Acad. Sci., 7, 1895, 435; Bacterium duplex Lehmann and
- Revised bj' Prof. E. G. D. Murray, University of Western Ontario, London, Canada,
April, 1955.
