The cross-reactivity of Shewanella fidelis lipopolysaccharide with anti-Proteus antibodies.

The serological cross-reactivity between lipopolysaccharides (LPS) of S. fidelis KMM3582(T) and rabbit anti-O P. mirabilis antibodies was tested. Using ELISA and Western blot cross-reactivity between S. fidelis LPS and antisera against P. mirabilis O14, O3 LPSs was found. The observed cross-reaction may suggest that anti-P. mirabilis S1959 (O3) antibodies may bind to the internal part of S. fidelis O-polysaccharides. A weak interaction between S. fidelis LPS and antiserum against P. mirabilis O13 in Western blot suggests that the absolute configuration of non-sugar "AlaLys" component (N(epsilon)-[(S)-l-carboxyethyl]-N(alpha)-(D-galacturonoyl)-L-lysine) may influence the affinity of antibodies for S. fidelis LPS.