title: The phosphate diester linkage of the peptidoglycan polysaccharide moieties of Micrococcus lysodeikticus cell wall.
abstract: The external polysaccharide is a major component of Micrococcus lysodeikticus cell wall and displays distinct composition. The complete structure of the external polysaccharide had been elucidated as a basis for investigation of the cell wall structure-function relation. However, the mode of attachment of the polysaccharide to the peptidoglycan through a phosphodiester was not clear due to limitations in structural and biosynthetic studies. The present study describes purification of a lysozyme-resistant nondialyzable high-molecular-weight fragment of cell wall and identifies the sugar, D-glucose, as the point of external polysaccharide attachment to the peptidoglycan through a phosphate diester. Kinetic studies for the acid-catalyzed release of external polysaccharide from the peptidoglycan were performed in parallel with synthetic [methyl-2-acetamido-3-O-(D-1-carboxyethyl)-2-deoxy-alpha-D- glucopyranoside-6-yl]-alpha-D-glucopyranosyl phosphate and alpha-D-glucopyranosyl phosphate and showed the presence of a phosphodiester linkage between external polysaccharide and peptidoglycan. In addition, type of phosphate residue and cross-linking between muramic acid and protein part have been determined.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000032:analysis; D002473:Cell Wall / Q000032:analysis; D002850:Chromatography, Gel; D008837:Micrococcus / Q000032:analysis*; D010457:Peptidoglycan / Q000302:isolation & purification*; D010710:Phosphates / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000302:isolation & purification*
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D010457:Peptidoglycan; D010710:Phosphates; D011135:Polysaccharides, Bacterial