[Ultrastructure of the L forms of Streptococcus group B]

The submicroscopic organization of the L-forms of beta-hemolytic streptococci of group B has been studied in the course of their cultivation. The L-forms of group B streptococci differ from those of group A streptococci by a higher growth rate. On the submicroscopic level, the activity of ATP-ase has been revealed on the internal side of the cytoplasmic membrane. Regularities in the localization of intramembranous particles sized 6-18 nm in the hydrophobic area of the membrane have been established by means of freezing-etching. With the adequate methods of fixation, the continuous three-layer structure of the cytoplasmic membrane can be determined in all elements of the L-form population.