STRUCTURE OF A HEXASACCHARIDE PROXIMAL TO THE HYDROPHOBIC REGION OF LIPOPOLYSACCHARIDES PRESENT IN BORDETELLA-PERTUSSIS ENDOTOXIN PREPARATIONS

A branched-chain hexasaccharide containing 3-deoxy-D-manno-oct-2-uloso nic acid was released by detergent-promoted hydrolysis from Bordetella pertussis endotoxin preparations that were first dephosphorylated wit h aqueous HF and then treated with nitrous acid. Its structure (2) [GR APHICS] was determined by chemical and physical methods. This hexasacc haride is present in all four lipopolysaccharides that make up the B. pertussis strain 1414 (phase 1) endotoxin preparations analysed, and i s situated near to the hydrophobic domains. An analogous structure rep orted previously (ref 7) is erroneous and should be disregarded.