Page:Bergey's manual of determinative bacteriology.djvu/538

cultures grow on blood agar containing 40 per cent bile. Litmus milk: Acid produced; may be curdled; litmus not reduced before curdling. Final pH in glucose broth, between 4.6 and 5.2. Acid from glucose, maltose, lactose, su- crose, trehalose and salicin. The majority of the cultures ferment inulin but not raffi- nose. Arabinose, xylose, glj^cerol, mannitol and sorbitol not fermented. Nearly all cultures synthesize a polysac- charide (dextran) from sucrose in broth culture (Niven, Kiziuta and White, Jour. Bact., 51 , 1946, 711) or on sucrose agar when incubated anaerobically (Hehre, Jour. Exp. Med., 83, 1946, 147). This polysaccharide cross reacts with type II pneumococcus antiserum. Starch usually not hydrolyzed. Gelatin not liquefied. Sodium hippurate not hydrolyzed. Escu- lin usually split. Ammonia produced from arginine. Relationships: Although the identity of non-hemolytic Streptococcus sanguis with the hemolytic group H streptococci has not yet been clearly established, their close re- lationship appears to warrant combining them into one species at this time. Further serological studies are needed to firmly es- tablish the validity of this grouping. Al- though most Streptococcus sanguis cultures react with group H sera, attempts to pre- pare group H sera ivora Streptococcus sanguis cultures have been unsuccessful. Source : The original group H strains were isolated from normal human throats. They were not believed to be associated with any serious human infections. Streptococcus sanguis was originally iso- lated from so-called vegetation on heart valves from cases of subacute bacterial endocarditis and appeared to be one of the most common streptococci associated with this disease. Occasionally isolated from in- fected sinuses and teeth and from house dust. Habitat: Unknown. Probably man. 7. Streptococcus anginosus Andrewes and Horder, 1906. (Andrewes and Horder, Lancet, 2, 1906, 70S, 775 and 852; Minute beta hemolytic streptococcus. Long and Bliss, Jour. Exp. Med., 60, 1934, 619; also see Long, Bliss andWalcott, ibid., 633, and Bliss, Jour. Bact., 83, 1937, 625.) an.gi.no'sus. L. adj. anginosus pertaining to angina. Minute cocci, one-half to two-thirds the size of Streptococcus pyogenes, occurring singly, in pairs, short chains and in small or large masses. Gram-positive, but may de- colorize readil3^ Serology: Comprises Lancefield's group F and type I group G. At least 4 serological types within group F have been established. The type-specific antigens in type I group F, and type I group G appear to be chem- ically and serologically identical. Action on blood: Very minute colonies appear on blood agar after incubation for 48 to 96 hours; they are surrounded by minute zones of beta hemolysis. The he- molytic zones may appear before the colo- nies are visible to the naked eye. Growth and hemolysis greatly aided by incubation under 10 per cent carbon dioxide (Deibel, Thesis, Univ. of Chicago, 1952). Soluble hemolysin produced, but may be difficult to demonstrate (Long and Bliss, Jour. Inf. Dis., 61, 1937, 96). Streptolysin O or S not produced. Non-hemolytic strains reported by Rantz (Jour. Inf. Dis., 71, 1942, 61). Colony forms : Matt colonies usually not produced. Under the microscope, colonies are finely granular and may appear wrinkled and crenated. Not fibrinolytic. Temperature relations: No growth at 10° C. and, with few exceptions, no growth at 45° C. Does not survive 60° C. for 30 minutes. Tolerance tests: Does not grow in broth containing 6.5 per cent NaCl or at pH 9.6. No growth on 40 per cent bile blood agar or in skim milk containing 0.1 per cent methylene blue. Litmus milk: Acid produced by the lac- tose-fermenting strains. Milk may be cur- dled by some strains. Litmus not reduced before curdling. Final pH in glucose broth, between 4.5 and 5.2. Acid from glucose, maltose, sucrose and salicin. Lactose and trehalose usually fer-