title: Location of O-methyl sugars in antigenic (lipo-)polysaccharides of photosynthetic bacteria and cyanobacteria.
abstract: An attempt was made to localize a number of O-methyl sugars in lipopolysaccharides and antigenic polysaccharides isolated from photosynthetic bacteria and from cyano-bacteria. Methylation analysis with [2H3]methyl iodide as methylating agent was the method of choice. One has to differentiate between (lipo-)polysaccharides having only trace amounts (less than 1% of polymer dry weight) of O-methyl sugars and those having them in larger amounts (more than 4% of polymer dry weight). In the former case O-methyl sugars occupy either non-reducing or reducing terminals. When present in larger quantities they may be present as part of each repeating unit either in chain-linked or in terminal positions or in both. A possible role of O-methyl sugars in biosynthesis of O-chains, and their contribution to the lipophilic character of the cell surface are discussed.
mesh_terms: D000942:Antigens, Bacterial / Q000032:analysis; D002844:Chromatium / Q000032:analysis / Q000276:immunology; D000458:Cyanobacteria / Q000032:analysis*; D008070:Lipopolysaccharides / Q000032:analysis* / Q000276:immunology; D008745:Methylation; D008759:Methylglycosides / Q000032:analysis*; D012241:Rhodopseudomonas / Q000032:analysis / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D008070:Lipopolysaccharides; D008759:Methylglycosides