FAMILY MICROOOCCACEAE 



241 



begins after first day and continues 

 rapidly. 



Agar colonies : Yellow to orange (Evans, 

 loc. cit.), pearly white (Hucker, loc. cit.). 



Agar stroke : Yellow to orange (Evans, 

 loc. cit.), pearly white (Hucker, ?oc. cii.), 

 luxuriant growth. 



Broth : Generally grows with smooth 

 turbidity although certain strains give 

 heavy precipitate with clear supernatant 

 fluid. 



Litmus milk: Acid, peptonized. Whej- 

 generally clear. 



Potato : Scanty white growth. Certain 

 strains may show yellow pigment. 



Indole not formed. 



Nitrites usually produced from ni- 

 trates. 



Acid from glucose, lactose, maltose, 

 mannitol and glycerol. Xo action on 

 raffinose. 



Forms dextrorotarj' lactic acid (Orla- 

 .Tensen, 1919, loc. cit.). 



Asparagin and urea decomposed by 

 some strains. 



Utilizes NH4H2PO4 as a source of nitro- 

 gen. 



Optimum temperature 22°C. 



Aerobic. 



Saprophytic. 



Source : Eight cultures from bovine 

 udder. 



Habitat: Milk and dairy products, 

 especially cheese, dairy utensils. 



9a. Micrococcus pyogenes var. aureus 

 (Rosenbach) Zopf . (Staphylococcus pyo- 

 genes aureus Rosenbach, Mikroorganis- 

 men bei den Wundinfectionskrankheiten 

 des Menschen, Wiesbaden, 1884, 19; 

 Staphylococcus aureus Rosenbach, ibid., 

 27; Micrococcus pyogenes var. aureus 

 Zopf, Die Spaltpilze, 3 Aufl.. 1885, 56; 

 Micrococcus aureus Zopf, ibid., 57; 

 Micrococcus pyogenes Lehmann and Xeu- 

 mann, Bakt. Diag., 1 Aufl., 2, 1896, 165; 

 Aiirococcus aureus Winslow and Rogers, 

 .Jour. Inf. Dis., 3, 1906, 554; Micrococcus 

 lactis varians Conn, Esten and Stocking, 

 Storrs Agr. Exp. Sta. Rept. for 1906, 



121 ; Staphylococcus pyogenes Andre wes 

 and Gordon, Rept. (35th) Med. Officer 

 Local Govt. Board, London, 1907, 549; 

 (Tetracoccus) Micrococcus pyogenes 

 aureus Orla-Jensen, The Lactic Acid 

 Bacteria, 1919, 81 ; Staphylococcus pyo- 

 genes-aureus Holland, Jour. Bact., 5, 

 1920, 225.) From Greek, pyon, pus; 

 M. h., -genes, producing. From Latin, 

 aureus, golden. 



Spheres: 0.8 to 1.0 micron, occurring 

 singl}', in pairs, in short chains, and in 

 irregular clumps. Xon-motile. Gram- 

 positive. 



Gelatin stab : Saccate liquefaction with 

 yellowish pellicle and yellow to orange 

 sediment. 



Agar colonies: Circular, smooth, yel- 

 lowish to orange, glistening, butyrous, 

 entire. 



Agar slant : Abundant, opaque, smooth, 

 flat, moist, yellowish to orange. 



Broth : Turbid with yellowish ring and 

 sediment, becoming clear. 



Litmus milk: Acid; coagulated. 



Potato: Abundant, orange, glistening. 



Indole not formed. 



Nitrites produced from nitrates. 



Acid from glucose, lactose, sucrose, 

 mannitol and glycerol, but not from 

 raffinose, salicin or inulin. 



Forms inactive or levorotary lactic 

 acid (Orla-Jensen, loc. cit.). 



Slight H2S formation. 



Starch not hydrolyzed. 



Does not utilize XH4H;P04, as a source 

 of nitrogen. 



Ammonia produced from peptone. 



Pathogenic. Individual strains vary 

 in their ability to produce hemolysin, 

 coagulase and other metabolic products. 



Certain strains, under favorable con- 

 ditions, produce not only exotoxins 

 (hematoxin, dermatoxin, lethal toxin, 

 etc.) but also a potent enterotoxin 

 which is a significant cause of food poi- 

 soning (Dolman and Wilson, Jour. 

 Immunology, 35, 1938. 13). 



Aerobic, facultative. 



Optimum temperature 37°C. 



Source : Isolated from pus in wounds. 



