Acetylhexosamine compounds enzymically released from Micrococcus lysodeikticus cell walls: III. The structure of di- and tetra-saccharides released from cell walls by lysozyme and Streptomyces F1 enzyme

Two compounds, both of which have been isolated from cell walls of Micrococcus lysodeikticus digested with lysozyme or Streptomyces F1 enzyme, have been identified as di- and tetra-saccharides. The reducing groups of the di- and tetra-saccharides and those of the high-molecular weight, non-dialysable compounds belong to muramic acid. [beta]-glucosidase yields free N-acetylglucosamine and N-acetylmuramic acid from the di- and tetra-saccharides. The proposed structure for the di-saccharide liberated by lysozyme and F1 is: 6-O-[beta]-N-acetylglucosaminyl-N-acetylmuramic acid. The tetra-saccharides isolated from lysozyme and F1 digests appear to be identical. The structure proposed for the tetra-saccharide isolated from lysozyme digested walls is: O-[beta]-N-acetylglucosaminyl-(I-->6)-O-[beta]-N-acetylmuraminyl-(I-->4)-O-[beta]-N-acetylglucosaminyl- (I-->6)-[beta]-N-acetylmuramic acid. Both lysozyme and Streptomyces F1 enzyme degrade di- and tetra-chitobiose, indicating their [beta](I-->4) N-acetyl hexosaminidase activity.