Generation of purpura-producing principle from pneumococcal cell walls.

The in vitro kinetics of muramic acid-alanine bond hydrolysis and pneumococcal purpura-producing principle generation by incubation of Streptococcus pneumoniae cell wall preparations with the bacterial autolysin N-acetylmuramyl-L-alanine amidase were similar. The generated purpura-producing principle preparation had a weight-average molecular weight of ca. 2.6 X 10(7) and possessed the glycan and teichoic acid constituents of the pneumococcal cell wall. The results support the idea that the pneumococcal purpura-producing principle is a high-molecular-weight, glycan-teichoic acid fragment released by hydrolysis of the muramic acid-alanine bonds in the bacterial cell wall.