Structure and serological characterization of an Nepsilon-[ (R) -1-carboxyethyl]-L-lysine-containing O-chain of the lipopolysaccharide of Proteus mirabilis O13
Swierzko, A.S.; Cedzyński, M.; Ziółkowski, A.; Senchenkova, S.N.; Perepelov, A.V.; Knirel, Y.A.; Kaca, W.
Archivum Immunologiae et Therapiae Experimentalis 49(2): 163-169
2001
ISSN/ISBN: 0004-069X PMID: 11348021 Document Number: 527310
In this paper we present the structure and describe serological properties of the O-specific polysaccharide of Proteus mirabilis O13 lipopolysaccharide, which contains a unique component: an amide of D-galacturonic acid (D-GalA) with an unusual amino acid, Nepsilon-[(R)-1-carboxyethyl]-L-lysine (alaninolysine, AlaLys). Selective chemical degradations of either GalA or AlaLys resulted in the loss of the serological reactivity of the polysaccharide with anti-O serum against P. mirabilis O13. Neither synthetic stereoisomers of AlaLys nor the isolated amide of GalA with AlaLys inhibited the reaction of the O-antiserum with the homologous lipopolysaccharide. The O-antiserum did not cross-react with the lipopolysaccharide of Providencia alcalifaciens O23 containing an amide of D-glucuronic acid with AlaLys. These data showed that both uronic acid and amino acid components of the amide play an important role in manifesting the P. mirabilis O13-specificity, but the full specific epitope also includes another O-specific polysaccharide component(s). A cross-reactivity of anti-O13 serum with some other P. mirabilis strains was observed and attributed to a common heat-stable antigen(s) different from the lipopolysaccharide.