The linkage between the polysaccharide and mucopeptide components of the cell wall of <i>Lactobacillus casei</i>

Abstract

1. The linkage between the polysaccharide and mucopeptide components of the cell wall of Lactobacillus casei is rapidly hydrolysed under mild acid-hydrolysis conditions. 2. The release of the polysaccharide is accompanied by the hydrolysis of an N-acetylhexosaminide linkage. The N-acetylhexosamine residue readily forms chromogen and it is concluded that it is substituted on C((3)) by the adjacent sugar. 3. Continued heating of the polysaccharide in acid results in a slower release of reactive N-acetylhexosamine due to the hydrolysis of glycosidic linkages within the polysaccharide. 4. After the linkage between the polysaccharide and mucopeptide has been hydrolysed, acid phosphatase will release approx. 40% of the total phosphorus as inorganic phosphate. 5. It is concluded that the polysaccharide component of the cell wall is joined through its reducing end group to a phosphate grouping in the mucopeptide.