The structure of the carbohydrate backbone of the core-lipid A region of the lipopolysaccharide from Proteus penneri strain 40: new Proteus strains containing open-chain acetal-linked N-acetylgalactosamine in the core part of the LPS.

Analysis of the core part of the LPS from several strains of Proteus revealed that P. penneri strains 2, 11, 19, 107, and P. vulgaris serotypes 04 and 08 have the same structure with a new type of linkage between monosaccharidesan open-chain acetal--that was previously determined for P. vulgaris OX2 and P. penneri 17. The LPS from P. penneri strain 40 contains the same structure substituted with one additional monosaccharide: [molecular structure: see text] where (1S)-GalaNAc1 is a residue of N-acetyl-D-galactosamine in the open-chain form. It is connected as a cyclic acetal to positions 4 and 6 of the galactosamine residue having a free amino group. All other sugars are in the pyranose form.