Page:Bergey's manual of determinative bacteriology.djvu/481

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FAMILY VII. MICROCOCCACEAE
459

Gr. adj. philus loving; M.L. adj. cryophilus frost-loving. Spherical cells, the average diameter be- ing 1.6 microns, occasional large cells measuring 3.6 and small cells measuring 1.0 micron in diameter, occurring singly, in pairs, in chains and in clusters. Nuclear bodies which vary in size and position have been observed in the cell. There is evidence that these bodies represent various stages of a mitotic and a meiotic process (DeLa- mater and Woodburn, Jour. Bact., 64, 1952, 793; Hunter, E.xp. Cell Res., 9, 1955, 231). However, compare Bisset (Jour. Bact., 67, 1954, 41). Non-motile; occasional cells are motile by means of peritrichous flagella. Gram-stains of veal infusion agar smears show Gram-positive cells with a predomi- nant number of Gram-negative cells irrespec- tive of the age of the culture. Gelatin: No liquefaction. Agar slant: Creamy white, glistening, fili- form, moderately heavy growth. Yeast extract agar: Growth same as above but heavier; old cultures become faint pink in color. Veal infusion agar: Growth same as above; old cultures become brownish yellow. Yeast e.xtract and nutrient broths : A ring is formed. Ulrich milk (Science, 99, 1941, 352) : Alka- line in 2 days; slight reduction of methylene blue indicator in 4 days. Indole not produced. Hydrogen sulfide not produced. No acid from glucose, lactose, sucrose, maltose, xylose, cellobiose, mannitol, dul- citol or salicin. Sodium citrate does not serve as a sole source of carbon. Nitrites not produced from nitrates. Ammonium phosphate does not serve as a sole source of nitrogen. Urease is produced. Oxidase not produced. Blood agar: No hemolysis. Catalase-positive. Aerobic. Temperature relations: Optimum, 9.8° C. Minimum, —4.0° C. Maximum, between 23° and 24° C. Optimum pH, between 6.8 and 7.2. Growth occurs between pH 5.5 and 9.5. Source: Isolated by McLean (Food Tech- nology, 6, 1951, 7) from a finished package of pork sausage prepared from frozen meat. Habitat: Found in frozen meat products so far as known. 7. Micrococcus conglomeratus Migula, 1900. (Citronengelber Diplococcus, Bumm, Der Mikroorganismus der gonorrhoischen Schleimhauterkrankungen, 1 Aufl., 1885, 17; Micrococcus citreus conglomeratus Fliigge, Die Mikroorganismen, 2 Aufl., 1886, 182; Migula, Syst. d. Bakt., 2, 1900, 146.) con.glo.me.ra'tus. L. part. adj. conglo- meratus rolled together. Spheres, 0.8 to 1.2 microns in diameter, occurring singly, in pairs, in fours and in large clumps. Non-motile. Gram-variable. Gelatin colonies: Small, circular, yellow with radiate margin. Gelatin stab: Slow crateriform liquefac- tion. Agar colonies: Luxuriant, moist, sulfur- yellow. Agar slant: Growth light yellow, plumose, slightly rugose, somewhat dull with raised center and transparent margin. Broth: Turbid, with light orange ring and sediment. Milk: Generally acid but not sufficient to curdle. Potato: No growth. Indole not produced. Acid from glucose and lactose generally, sometimes from sucrose. Mannitol and glycerol generally not fermented. Starch not hydrolyzed. Nitrites produced from nitrates. Ammonia produced from peptone. Utilizes NH4H2PO4 as a source of nitro- gen. Blood not hemolyzed. Non-pathogenic. Aerobic. Optimum temperature, 25° C. Resistant to drying and heat. Source: Found in gonorrhoea! pus and in dust. Habitat: Infections, milk, dairy products, dairy utensils, water. Common.