Immunoelectron microscopic localization of T proteins in the cell wall of Streptococcus pyogenes.

T proteins of Streptococcus pyogenes (group A streptococci) were localized by means of immunochromatographical isolated anti-T-antibodies. For the electron microscopical detection both the direct and the indirect immunoferritin techniques were used. The arrangement of the ferritin particles showed, that the T proteins are evenly distributed on the whole cell surface. They are immediately bound to the outer layer of the cell wall or to only short filaments. On isolated cell walls the T protein was detected only on the outer surface.