Description:
<jats:p>Mild acid hydrolysis of the P<jats:sup>+</jats:sup> lipopolysaccharide of <jats:italic>Salmonella minnesota</jats:italic> mRz, a UDP‐glucose synthetase‐less mutant, leads to the formation of 5 degradation products whose structures were studied. Free 2‐keto‐3‐deoxyoctonate (KDO), KDO‐7‐phosphorylethanolamine, and fraction P<jats:sup>−</jats:sup> (Hep‐Hep‐KDO) have been identified previously as degradation products of a P<jats:sup>−</jats:sup> lipopolysaccharide (glycolipid). Fractions P<jats:sup>+</jats:sup> (Hep‐(Hep‐4‐phosphate)‐KDO) and PPN (Hep‐(Hep‐4‐pyrophosphorylethanolamine)‐KDO) occur only in the P<jats:sup>+</jats:sup> mutant. It was shown that fraction P<jats:sup>+</jats:sup> is not an artifact which was formed from fraction PPN during partial hydrolysis. The simultaneous occurrence of fractions P<jats:sup>+</jats:sup> and PPN reflects microheterogenicity of the lipopolysaccharide. Possible reasons for this are discussed.</jats:p>