HEMOLYTIC STAPHYLOCOCCI 7 



3. The figures for the numerical counts show that there is. an 

 increase in the number of staphylococci until the third day, when a 

 maximum is reached. From then on there is a sharp decrease in 

 numbers, indicating that growth of an active nature at least has come 

 to a cessation. If the production of hemolysins and the numerical 

 counts had shown a parallelism, it could have been reasonably assumed 

 that the hemolysin were a true secretion product and a definite hemo- 

 toxin. Since they show no such parallelism, however, the hemolysin 

 must be of some other nature. 



4. The course of proteolysis or amine acidity runs a definitely 

 parallel course to the curve of hemolysin production. The suggestion 

 offered itself that if not directly associated, then some close relationship 

 must exist between the two. Further study reveals the following con- 

 catenation of events: (1) the period of maximum growth occurs on 

 the third and fourth day; (2) the maximum production of amino 

 acidity occurs on the seventh and eighth days; (3) the maximum pro- 

 duction of hemolysins occurs on the ninth and tenth days. Stated in 

 another way, the growth period precedes the amino acidity period, which 

 in turn precedes the hemolysin production period. It would seem from 

 such an interrelated process that the production of hemolysins is a 

 proteolytic process and perhaps even autolytic. 



There is one other point of interest brought out by this experiment. 

 Although there is an increase in amino acidity, there is no corresponding 

 decrease in proteose content. This is probably due to the fact that the 

 biuret test, used in determining the amount of proteose present, shows 

 the presence of substances other than proteose; so that even if proteose 

 were proteolyzed to form polypeptides, peptides and the higher amino 

 acids the intensity of the color would still remain the same. One other 

 point it shows that the production of erepsin by staphylococci enables 

 them to attack peptones and proteoses. 



5. Following the suggestion offered in the foregoing experiment, 

 the next step was to determine what role autolysis plays in hemolysis. 

 For this purpose 24-hour cultures were inoculated in Erlenmeyer flasks 

 (10% serum broth), and incubated at 37 C. for 5 days. This culture 

 was then distributed in equal volumes into test tubes. To one series 

 was added 0.25% phenol, to a second 10% HCC13; a third series was 

 incubated at 45 C. ; and a fourth was left untreated and incubated with 

 the first and second series at 37 C. The object of this procedure was 

 to determine whether after the maximum growth period was reached 



