3-Deoxy-d-manno-oct-2-ulosonic acid or keto-deoxyoctulosonate (KDO) is an ulosonic acid of a 2-ketooctose which is used by bacteria in the synthesis of lipopolysaccharides. The d-manno prefix indicates that the four chiral centers have the same configuration as d-mannose. 3-Deoxy-d-manno-oct-2-ulosonic acid or keto-deoxyoctulosonate (KDO) is an ulosonic acid of a 2-ketooctose which is used by bacteria in the synthesis of lipopolysaccharides. The d-manno prefix indicates that the four chiral centers have the same configuration as d-mannose.