172 



THE ACTIXOMYCETES, Vol. I 



-4 N. polychromoganat 

 "O S. grium 



• S. bobilio« 



° N. rubra 



80 



100 



120 



TIME (MINUTES) 



Figure 74. Liberation of reducing sugars (expressed as per cent of dry weight of cell walls), on 1 

 A' HCl hydrolysis at 100°C of cultures of Streptomijces and Nocardia (Reproduced from: Romano, A. H. 

 and Sohler, A. J. Bacteriol. 72: 867, 1956). 



Lieske reported in 1921 that certain acti- 

 nomycetes have the capacity to dissolve bac- 

 teria and other microorganisms. A suspen- 

 sion of dead bacteria, such as staphylococci, 

 was mixed with agar and poured into plates. 

 These plates were inoculated with actinomy- 

 cete cultures and incubated. The actinomy- 

 cetes were able to dissolve the bacterial cells, 

 as shown by the clear zones produced around 

 the actinomycete colonies. Lieske demon- 

 strated further that living bacteria likewise 

 may be dissolved; both spore-forming and 

 nonspore-forming gram-positive and gram- 

 negative bacteria were sensitive to the action 

 of certain actinomycetes. Lieske considered 

 this effect to be due to bacteriolytic mechan- 

 isms of an enzymatic nature. It may be of 

 interest to (juote Lieske, because of the pres- 

 ent great significance of the lytic mechanisms 

 of actinomycetes. It is of particular interest 

 to note that he questioned, although he did 

 not exclude, the therapeutic potentialities of 

 this phenomenon. He .said: 



"Ob die bakteriolytischen Enzyme der 



Strahlenpilze einmal \o\\ therapeutischer Be- 

 deutung werden konnen, ist fraglich, aber 

 immerhin nicht ausgeschlossen. Die grossen 

 Erwartungen, die man auf die Pyocyanase, 

 den entsprechenden Stoff des Bacterium py- 

 ocyaneum gesetzt hat, sind leider bisher 

 nicht erfiillt worden. Dass mit den Enzymen 

 der Strahlenpilze, die jedenfalls eine bedeu- 

 tende bakterizide Wirkung haben, bei An- 

 wendung geeigneter Methoden bessere Ergeb- 

 nisse erzielt werden konnen als mit Pyo- 

 cyanase, ist keineswegs unmoglich." 



In 1928, Lieske again compared the phe- 

 nomenon of bacterial lysis brought about l\v 

 cultures of actinom3^cetes with the action of 

 pyocyanase, a bacterial product, not enzy- 

 matic in nature. He noted that no further 

 study was made of the actinomycete prepara- 

 tion (which he considered to be an enzyme) 

 and that it was not known whether it, like 

 pyocyanase, could be used for curative pur- 

 poses. 



In 1924, Gratia and associates suspended 

 dead cells of staphylococci and of other bac- 



\ 



