The Serological Identification of Streptococcus Zymogenes with the Lancefield Group D.

In their study of Streptococcus zymogenes, Sherman, Stark and Mauer (1937) stated that on the basis of a physiological study of a few of Dr. Lancefield's cultures, the Lancefield group D hemolytic streptococcus and Streptococcus zymogenes appeared to be the same. There was nothing essentially new in this suggestion: Lancefield and Hare (1935) had previously stated that the group D streptococci were in fact more closely related to Streptococcus fecalis than to Streptococcus pyogenes; Hare and Maxted (1935) isolated group D streptococci from human feces and related them to the "hemolytic enterococci" of previous workers; and Houston (1936) had mentioned Streptococcus zymogenes as one of the enterococci which belong in one serological group by the Lancefield method. As the studies in this laboratory of the members of the enterococcus division of the streptococci have been somewhat more detailed with reference to the identity of the several "species" belonging to this group, than have most of the papers which have dealt somewhat loosely with "enterococci," it seemed desirable to classify by the Lancefield precipitin technique a collection of these more extensively studied cultures which have been specifically identified as Streptococcus zymogenes. For this purpose, 76 cultures have been studied, 70 of these being isolated from human feces and six from pasteurized milk.