Isolation and Reversion of L Forms of Betahemolytic Streptococci

Abstract

L colonies were isolated from 14 strains of streptococci of which 13 were group A and one was group C. Certain of the cultural properties were investigated. The sodium chloride concentration was found critical for survival of L forms and for their development from streptococci. Strains of streptococci that rarely produced L colonies upon first exposure to penicillin were induced into this form by using a "blind" transfer technic. The recovery of streptococci of the original serological groups and types was accomplished from 9 out of 11 strains of L forms. Yeast extract appeared to favor the return of the coccal form in the cultures.