ANTIBACTERIAL EFFECTS 



127 



the same organism when grown under identical conditions vary greatly 

 in the production of the antibiotic substance is brought out in Table 27. 



PenicilUum notatum-chrysogenum Grouf 



Because of the production by these organisms of penicillin, which has 

 already found a wide practical application, this group of fungi deserves 

 first consideration. Fleming (265) first observed that a fungus culture 

 growing on a staphylococcus plate brought about destruction of the bac- 

 teria, as shown by the fact that the colonies became transparent and 

 were undergoing lysis. The fungus was isolated in pure culture and was 

 later identified as P. notatum. It was found to possess marked bacterio- 

 static and bactericidal properties for some of the common pathogenic 

 bacteria, largely the gram-positive cocci and the staphylococci, the strep- 

 tococci, the diphtheria organism, and the gonococci and meningococci j 



TABLE 27, PRODUCTION OF CLAVACIN BY FIFTEEN STRAINS OF 

 ASPERGILLUS CLAVATUS 



From Waksman and Schatz (942). 



Note. Eight-day-old culture was used for extraction of the clavacin. 



