Identification of a lytic enzyme ofClostridium acetobutylicumthat degrades choline-containing pneumococcal cell walls

A protein that degrades pneumococcal walls containing choline, but not ethanolamine, in the teichoic acids has been isolated and purified from supernatants obtained from cultures of Clostridium acetobutylicum.The analyses of the degradation products of [3H]choline-labeled cell walls treated with this enzyme indicated that the purified protein, showing an apparent M r of 115000, is an N-acetylmuramyl-L-alanine amidase.Our results also suggest that C. acetobutylicum contains choline in its cell wall.