470 CORYNEBACTERIUM 



Growth. — Grows freely on ordinary media, forming large succulent colonies of irregular 

 shape and pale pink colour. On potato the growth is moist, thick, and pale pink, later 

 becoming deep reddish yellow. Slate to black colonies on tellurite blood agar. Grows 

 well between 18° and 37° C. 



Resistance. — Said by Karlson, Moses and Feldman (1940) to be unusually resistant 

 to oxahc acid, which is sometimes used for the destruction of non-acid-fast bacUli. 



Biochemical Reactions. — No fermentation of sugars. Poor growth in litmus milk 

 with no obvious change. No haemolysis. No Uquefaction of coagulated serum or gelatin. 

 Indole negative. Nitrates reduced to nitrites. SUght HjS production. Catalase formed. 



Antigenic Structure. — Strain specificity said to be marked, so that the agglutination 

 reaction is of little help in identification. By complement fixation, however, a species- 

 specific antigen can be demonstrated (Bruner, Dimock, and Edwards 1939). 



Pathogenicity. — Gives rise under natural conditions to pyaemia in foals, characterized 

 by a suppurative bronchopneumonia with intense purulent infiltration of the adjoining 

 lymph nodes, and sometimes to intestinal ulceration and abscess formation in the mesenteric 

 lymph nodes. Probably non-pathogenic for swine, though frequently present in the 

 submaxillary lymph nodes. Experimentally, the natural disease can be reproduced by 

 intratracheal inoculation of foals. Subcutaneous inoculation produces local abscess 

 formation with involvement of the focal lymph nodes in horses, pigs, and goats. Gives 

 rise to peritonitis, not always fatal, when inoculated intraperitoneally into guinea-pigs. 



C. renale 



This organism was first described by Enderlen ( 1890-91), but it is very doubtful whether 

 all the strains of diphtheroid bacilli that have since been isolated from pyelitis in cattle 

 were identical with the bacUlus isolated by him ; and it is by no means certain that the 

 organism described by more recent workers is entitled to specific rank. It seems quite 

 clear, however, that this organism differs in several ways from C. pyogenes, with which it 

 has often been confused. The incomplete description that follows is taken mainly from the 

 papers of Jones and Little (1925, 1930) and Merchant (1935) and is given with considerable 

 reserve. 



Morphology. — C. renale is a typical Gram-positive barred diphtheroid, showing 

 rmmerous metachromatic granules, and considerable pleomorphism. 



Growth. — On serum agar gives moist, raised colonies showing a pigmentation that 

 varies from cream to yellow. Later the growth becomes drier. 



Biochemical Reactions. — Most strains that have been examined have fermented 

 dextrose alone, with the production of acid. According to Merchant (1935), Isevulose 

 and mannose may also be fermented. Gelatin is not liquefied. No hsemolysin is produced. 



Antigenic Structure. — The few data available (see Merchant 1935) are insufficient 

 to allow any adequate description. 



Pathogenicity. — The organism has been isolated by several observers from cattle 

 suffering from pyelitis; and Jones and Little (1925, 1930) have reproduced the disease 

 experimentally in these animals by the injection of pure cultures. No data are available 

 with regard to its pathogenicity for laboratory animals. 



C. murium 



(Synonym. C. pseudotuberculosis murium.) 



Isolated from a mouse by Kutscher in 1894 and by Bongert in 1901. It has since 

 been isolated by several observers (Andrewes et al. 1923). 



Morphology. — In films from cultures on Loefflers medium the appearances are very 

 similar to those presented by C. avis, or by some strains of C. diphtherice (see Fig. 87). 



