Studies on the Hemolytic Streptococcus1

Aaron H. Stock
1939 Journal of Bacteriology  
In preliminary experiments designed to isolate pure erythrogenic toxin from streptococcal filtrates, extraneous products were encountered which complicated the separation. In this paper, five such products-a peptone polysaccharide, a uronic acid polysaccharide, a yellow "oil," syrupy proteins, and a "nucleoprotein" fraction-are to be discussed in sequence. The results are presented in some detail because they seem to be of value to the bacteriologist and the biochemist. In this study, cultures
more » ... is study, cultures of the NY5 strain of hemolytic streptococcus were made in three types of mediums which were used in sequence. Alcohol was employed to precipitate the toxin. The first medium consisted of Parke-Davis peptone and meat infusion. The small amount of toxin precipitated from the culture filtrate was associated with a peptone polysaccharide (Stock, 1937 ) that has been found to have no relationship to the toxin. The second type of medium was free from peptone polysaccharide. The small amount of toxin that was precipitated from such culture filtrates was mixed with two other substances, a uronic acid polysaccharide and a yellow "oil." In attempting to obtain all the toxin from the filtrates, syrupy protein products were precipitated. Consequently, a third type of medium was devised, one that did not contain readily precipitable polysac-
doi:10.1128/jb.38.5.511-524.1939 fatcat:2fqouorsivdmxftm6ol4xrspe4