it was found that b. fragilis lipid a consists of a beta-d-glucosaminyl- ( 1-6 ) -d-glucosaminyl-1-o-phosphate backbone whose hydroxyl groups in positions 4 , 4 ' and 6 ' are free , the latter serving as the attachment site for the polysaccharide component in lipopolysaccharide .
C0023767
lipid a
C0023810
lipopolysaccharide