ACTINOMYCES MVRI8 385 



Gelatin Siab.—l days at 20° C. Moderate filiform growth of confluent, greyish-white, 

 feathery colonies ; extending to bottom of tube. Slightly raised surface growth, 

 3 mm. in diameter. After 3 weeks the growth near the surface is orange-pink. 

 Liquefaction unusual. 



Broth. — 24 hours at 37° C. Moderate growth ; ropy or membranous sediment, not dis« 

 integrating on shaking ; ring growth and finely granular almost invisible surface 

 pellicle ; turbidity absent, or shght and finely granular. 7 days, thick surface 

 pellicle, extending up sides of tube ; dry, dull, and scaly with pinkish-yeUow or 

 orange nodules in places ; heavy floccular deposit, pinkish in colour. No odour. 



Glucose Agar Shake. — 8 days at 37° C. Good growth confined to surface, except for a 

 few tiny colonies in upper 5 mm. of medium. Surface growth is thick, raised, 

 confluent, dull, greyish-white with several secondary colonies developing on it. 

 Sometimes surface growth is heaped-up, yellowish-brown, and of worm-cast type 

 with no colonies below surface. 21 days, growth is brick-red or yellowish-orange 

 in colour. 



Loefjier^s Serum. — 24 hours at 37° C. Good, raised, moist, glistening confluent growth 

 with nodular surface and lobate edge. 24 days, no liquefaction. 



Dorset Egg. — 10 days at 37° C. Good, confluent, raised, yellowish growth with nodular 

 surface and edge formed of single colonies. 24 days, no liquefaction. 



MacConkeys Agar. — 6 days at 37° C. Growth of small, 0-1 mm. in diameter, pinkish, 

 opaque colonies ; growth very poor compared to that on agar. In liquid medium 

 there is good growth with a heavy granular deposit. 



Potato. — 24 hours at 37° C. Poor, slightly raised, chalky-white growth with powdery 

 surface. Later, growth may turn yellowish-orange or ochre-brown. 



Resistance. — Cultures remain viable for months. 



Metabolism. — Aerobic. No growth under strict anaerobic conditions. Optimum tempera- 

 ture 37° C ; grows at 20° C. No hsemolysin for horse red cells. Yellowish, orange, 

 or pink pigment formed, particularly in old cultures stood at room temperature. 

 Growth is improved by glucose, sometimes by serum. 



Biochemical. — No fermentation of sugars. Litmus milk turned slightly alkaline in 6 

 days ; may be slowly peptonized Indole — ; M.R. — ; V.P. — ; Nitrate reduc- 

 tion + ; NHg-f ; H,S very slight + ; Catalase + ; M.B. reduction—. 



Pathogenicity. — Appears to be non-pathogenic to laljoratory animals. 



Actinomyces muris 



Synonyms. — Streptothrix rmiris ratti 



Schottmiiller ; Streptobacillus mon- ' >S>^ 



Hi for mis Levaditi. 

 Isolation. — Isolated by Schottmiiller ^ . 



(1914) from human patients bitten 



by rats. 

 Habitat. — Natxiral parasite inhabiting / -'^ "^ \ '^ 



the nasopharynx of rats (Strange- '^ "^ "^ / 



ways 1933 ). "" T-n^S , ^ \ 



Morphology. — Loeffler^s serum at 37° C. 



Slender branching filaments, 0-4- ^ 



0-6 /J. wide, growing in interwoven 



masses. After 18-24 hours frag- 

 mentation of the filaments sets /' , 



in, and many of the filaments are '^* 



replaced by chains of bacfllary or 



coccoid bodies. Very marked 



pleomorphism. Occasional fila- p^^ 64.— Actinomyces muris. From a Loeffler 



meats show spherical, oval, fusi- slope, 2 days, 37° C. aerobically ( x 1000). 



P.B. O 





i-,^ 



