STRUCTURAL STUDIES ON A CELL-WALL POLYSACCHARIDE PREPARATION OF LACTOCOCCUS-LACTIS SUBSPECIES CREMORIS H414

A cell wall polysaccharide preparation of Lactococcus lactis subsp. cr emoris H414 was isolated by nitrous acid extraction, and purified by g el filtration and anion-exchange chromatography. Oligosaccharide fragm ents, obtained by partial acid hydrolysis or alkaline hydrolysis, were studied by means of monosaccharide analysis, methylation analysis, FA B-MS, EI-MS, and ()1H NMR spectroscopy. In addition H-1, C-13, and P- 31 NMR spectroscopy, including two-dimensional homo- and heteronuclear measurements, were performed on the native polysaccharide. Combinatio n of the various results demonstrated that in the polysaccharide prepa ration two repeating units with the structures -->2)-alpha-L-Rhap-(1- ->3)-alpha-D-Galp-(1-->(n) and eta-D-GalpNAc-(1-->1)-Ribitol-(5-phosp hate-->(m), respectively, can be recognized. So far, a covalent linka ge between both polymers could not be confirmed nor be excluded.