Oligosaccharides are the carbohydrates which are made of approximately 3-10 units of monosaccharide. Oligosaccharides are bound to the lipids or the proteins to form the glycolipids and the glycoproteins respectively by the O-glycosidic or the N-glycosidic linkages. <u>They are found in the bacterial lipopolysaccharides especially cell wall lipopolysaccharides of the Gram negative bacteria. Llipopolysaccharide of the Gram negative bacteria consists of O-antigen that consists of repeated oligosaccharide units.</u>
