Page:Bergey's manual of determinative bacteriology.djvu/545

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FAMILY X. LACTOBACILLACEAE
523

Action on blood: Greening (alpha hemo- lytic) to indifferent (gamma hemolytic). Abundant growth in broth media con- taining fermentable carbohydrate with the production of uniform turbidity and heavy sediment. Some strains are actively motile (Leven- sen, Ann. Inst. Past., 60, 1938, 99; Bruner, Edwards, Doll and Moran, Cornell Veteri- narian, 38, 1948, 313; Auerbach and Felsen- feld, Jour. Bact., 56, 1948, 587). A few strains are reported that are yellow pigmented (Hannay, Jour. Gen. Microbiol., 4, 1950, 294). Not fibrinolytic. Temperature relations: Growth at 10° and 45° C. Survives 60° C. for 30 minutes. Tolerance tests: Growth in broth contain- ing 6.5 per cent NaCl. Growth at pH 9.6 (Sherman and Stark, Jour. Dairy Sci., 17, 1934, 525; Shattock and Hirsch, Jour. Path. Bact., 69, 1947, 495). Growth in milk con- taining 0.1 per cent methylene l)lue. Growth on 40 per cent and higher concentrations of bile in blood agar. Litmus milk: Acidified, usually curdled with complete reduction of litmus before curdling. Some cultures do not reduce lit- mus before curdling. Final pH in glucose broth, between 4.0 and 4.4. Acid from glucose, maltose, lactose, trehalose and salicin. All cultures ferment glycerol, although this substance may be fermented only under aerobic conditions by some strains (Gunsalus and Sherman, Jour. Bact., 45, 1943, 155). Mannitol and sorbitol are fermented with only occasional ex- ceptions. Arabinose and sucrose may or may not be fermented. Inulin and raffinose are seldom fermented. Some strains are able to ferment citric acid in the absence of any fermentable car- bohydrate with the production of acetic acid, carbon dioxide, formic acid and lactic acid (Campbell and Gunsalus, Jour. Bact., 48, 1944, 71). No polysaccharide is synthesized from sucrose. Starch and gelatin not hydrolyzed. Sodium hippurate may or may not be hy- drolyzed. Esculin split. Ammonia produced from arginine. Tyrosine is decarboxylated with the pro- duction of tyramine and carbon dioxide. Distinctive characters: This species and the other members of the enterococcus group are easily distinguished from the other Streptococcus species by their wide temperature limits of growth, their salt tolerance and their ability to initiate growth at pH 9.6. They are also considerably more tolerant to penicillin than the other streptococci, most strains being able to grow in the presence of 0.5 to 1.0 unit of this antibiotic per ml. All enterococci are dis- tinctive in their ability to decarboxylate tyrosine. Source : Human feces and the intestine of many warm-blooded animals. Occasionally encountered in urinary infections and in the blood stream and heart lesions in subacute endocarditis cases. Associated with Euro- pean foul-brood of bees; found in milk and dairy products. Has been associated with mild outbreaks of food poisoning. Habitat: Intestines of humans and many other warm-blooded animals. 16a. Streptococcus faecalis var. lique- faciens (Sternberg, 1893, emend. Orla- Jensen, 1919) Mattick, 1947. {Streptococcus liquefaciens Sternberg*, Manual of Bac- teriology, 1893, 613; Orla-Jensen, The Lac- tic Acid Bacteria, 1919, 142; Mattick, Proc. Fourth Internat. Cong, for Microbiology, Copenhagen, 1947, 519.) li.que.fa'ci.ens. L. part. adj. liquefaciens liquefying. This variety was regarded as a separate species. Streptococcus liquefaciens, in the Manual, 6th ed., 1948, 326, but it is believed that the differences are not sufficient to warrant species distinction. This variety possesses the same characteristics as Strep- tococcus faecalis except as given below. It is a member of the enterococcus group and Lancefield's group D. It can not be dis-

  • Streptococcus liquefaciens Frankland and Frankland, 1888 (Phil. Trans. Roy. Soc.

London, 178, B, 1888, 264), may have been an organism identical with Sternberg's; it was described as producing a yellow pigment, as do certain strains of Streptococcus faecalis.