LIPO-OLIGOSACCHARIDES OF CAMPYLOBACTER-JEJUNI SEROTYPE O-10 - STRUCTURES OF CORE OLIGOSACCHARIDE REGIONS FROM A BACTERIAL ISOLATE FROM A PATIENT WITH THE MILLER-FISHER-SYNDROME AND FROM THE SEROTYPE REFERENCE STRAIN

Lipo-oligosaccharide (LOSa) was obtained by phenol-water extraction of bacterial cells of an isolate PG 836, identified as Campylobacter jej uni serotype O:10, from a patient who subsequently developed the Mille r-Fisher syndrome (MFS). The product was separated into a water-insolu ble gel of low M-r and a water-soluble component of high M-r. The stru cture of the core oligosaccharide region in LOSa is reported herein fo r comparison with LOSb from the C. jejuni O:10 reference strain, and i s based on investigations carried out on: (1) O-deacylated LOSa; (2) t he core oligosaccharide (OS 1a) liberated on acetic acid hydrolysis of the ketosidic linkages to lipid A, with accompanying loss of N-acetyl neuraminic acid residues; (3) the product of the removal of phosphate residues from OS la to give OS 2a; and (4) the Smith degradation of OS 2a to yield a mixture of Os 3a and OS 4a. The results revealed that t he core oligosaccharide region in LOSa from the MFS bacterial isolate had chains (1a), of which some were terminated by an N-acetylneuramino biose [Neu5Ac(alpha 2-8)Neu5Ac] unit in a GD(3) [Neu5Ac-Neu5Ac-Gal] ep itope, and the inner regions of which were different from those of oth er C, jejuni serotypes. Similar experiments on LOSb from bacterial cel ls of the C. jejuni O:10 reference strain showed that the core oligosa ccharide unit [1a, R = P (phosphoric monoester)] of LOSa from the MFS isolate was more uniformly complete than that of the O:10 reference st rain [1b, R = AEP (2-aminoethylphosphate)] differing in the nature of the phosphate substituent at the inner heptose residue. The close stru ctural relationship of LOSa from the MFS associated bacterium to LOSb from the O:10 reference strain runs parallel to that of the previously studied Guillain-Bant syndrome (GBS) associated bacterium typed as C. jejuni O:19 in comparison with the lipo-oligosaccharide from the refe rence strain. Preliminary studies on the high M-r components showed th at those from the O:10 strains were indistinguishable from each other, but were structurally unrelated to those from the GBS associated C. j ejuni serotype O:19 isolates and the O:19 reference strain [G.O. Aspin all, A.G. McDonald, and H. Pang, Biochemistry, 33 (1994) 250-255]. (C) 1998 Elsevier Science Ltd.