Structural studies of the O-antigenic polysaccharide of the bovine mastitis isolate Escherichia coli serotype O174.

Escherichia coli is one of the major causative agents of bovine mastitis, a disease affecting dairy herds. The lipopolysaccharide (LPS) of E. coli was plays a prominent role during infection. Here, we report on the O-antigen chemical structure of the LPS from Escherichia coli strain 2188 (serotype O174:H28) isolated from a mastitis-diseased cow. The structure of the OPS was analyzed by 1 and 2D NMR spectroscopy, and methylation analysis, which identified the branched repeating tetrasaccharide biological unit. [structure: see text].