L^ Til" MlX'llAMSMS 



169 



was clianuicd to alkaline. In hroth cultures, 

 lysis took i)la('(> in 2 to :\ weeks, and was as- 

 sociated with the t'onnalion u[' a nonenzy- 

 niatic and nontransniissible lytic factor. 



Diniitriev and Soutiex- (I!) 17) su<i;f^ested 

 that tlu> lysed preparation of patho<;enic ac- 

 tinoniycetes, desii>;natetl as actinolysate, 

 could be utilized in the therapy of infectious 

 caused !>>' these organisms. They empha- 

 sized, howe\er, that sucli ]M-eparations must 

 first be })urified and concentrated. 



Krassilniko\' and Koreniako (IDi^S) stud- 

 ied the phenomenon of autolysis amonji; 

 those actinomycetes that are now known to 

 belong to species of Streptomyccs and .Vo- 

 cardia. In the streptomyces, either the entire 

 colony underwent lysis or only partial lysis 

 occurnnl, usually beginning in the center of 

 the colony and proceeding to the perijjhery; 

 the colony liecame slimy, flat, and trans- 

 parent, finally changing to a viscous consist- 

 ency. In the nocardias, the colonies were lysed 

 simultaneously throughout the entire sur- 

 face. The phenomenon of autolysis was not 

 accompanied by the formation of saltants or 

 new races. The lytic substances were pro- 

 duced by the cells themselves and were not 

 of outside origin. Autolysis usually began at 

 the time of aging of the culture; at ()0 to 

 70°C, complete lysis occurred in a few min- 

 utes. Any factors retarding growth of tlie or- 

 ganism were found to hasten lysis. Thus, a 

 culture of A^. cifrea underwent lysis under 

 suboptimal conditions of temperature, or un- 

 der the influence of ether, chloi-oform, ben- 

 zol, acetone, and other \()latile conii)ounds. 

 Autolysis was also found to be hastened by 

 the secretion products of certain spore-form- 

 ing bacteria. The rapidity of lysis. caused by 

 these factors varied from a few minutes (at 

 ()0°C) to several hours. 



The agent responsible for autolysis was re- 

 sistant to heat; even 1 hour at 80°C had no 

 effect but it was inactivated in 5 minutes at 

 100°C. In contradistinction to phage, it 

 acted not only upon li\ing cells but also 



uj^on dead cells. The conclusion was reached 

 that the autolytic substance of actinomy- 

 cetes isi)roduced in the cells themselves and 

 is liberated at the nioniciit of their decompo- 

 sition. 



Krassilnikox and Koicniako suggested a 

 I'e.semblance of autolysis among actinomy- 

 cetes to phage formation by bacteria. The 

 lytic factor of actinomycetes was found to be 

 highly specific, since it had no effect upon 

 other species or even upon other .strains of 

 the same organism; it was thus distinguished 

 fi-om lysozyme. Different strains of an or- 

 ganism underwent lysis with varying degrees 

 of rai)idity. Production of the lytic factor or 

 its mode of action was believed to be differ- 

 ent for the different organisms. 



Of the 1000 or more freshly isolated cul- 

 tures studied by Krassilnikov, only a few 

 were able to undergo autolj'sis. A culture of 

 an organism that gave, when freshly iso- 

 lated, heavy compact growth co^'ered with 

 white aerial mycelium, produced, on contin- 

 uous transfer, flat, smooth, and somewhat 

 moist colonies that lost the pi"operty of form- 

 ing aerial mycelium. Gradually the growth of 

 the culture was reduced to a thin slimy film, 

 and, on repeated transfer, became trans- 

 parent, until the culture finally ceased to 

 grow altogether; all attempts to keep it alive 

 were unsuccessful. ( )ther cultures of actino- 

 mycetes belonging to different morphological 

 and physiological grcnips showed similar ly- 

 sis, although in different degrees. 



A colony may not undergo complete lysis. 

 Only certain sectors or spots may dissolve, 

 the unlysed portion of the colony remaining 

 unaffected. Frecpiently, lysis begins in the 

 center of the growth and proceeds to the 

 periphery. The mechanism of lysis among the 

 pathogenic actinomycetes is similar to that 

 occurring among the sa])rophytic forms, but 

 the rat(> of lysis is more I'apid. Organic media 

 are favorable to the lytic process. When a 

 culture haxing th(> capacity to undergo lysis 

 is grown on ])lates at 2.)°C, then incubated 



