Henrianna Pang

Structures of the O chains from lipopolysaccharides of Campylobacter jejuni serotypes O:23 and O:36

Lipopolysaccharides of C. jejuni serotypes O:23 and O:36 have been shown to contain structurally variable O polysaccharide chains with repeating units of four closely-related types: ----3)-beta-D-GlcpNAc-(1----3)-alpha-D-Galp-(1----2)-6d-alpha-D-alt-H epp-(1---- , ----3)-beta-D-GlcpNAc-(1----3)-alpha-D-Galp-(1----2)-6d-3-Me-alpha-D-alt -Hepp- (1----, ----3)-beta-D-GlcpNAc-(1----3)-alpha-D-Galp-(1----2)-D-glycero-alpha-D-a lt-Hepp - (1----, and ----3)-beta-D-GlcpNAc-(1----3)-alpha-D-Galp-(1----2)-3-Me-D-glycero-alph a-D-alt - Hepp-(1----. Structural methods included 1H- and 13C-NMR spectroscopy, methylation linkage analysis, fast atom bombardment mass spectrometry of methylated glycans, and selective fragmentations by the Smith degradation and N-deacetylation-nitrous acid deamination.

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 jejuni serotype O:10, from a patient who subsequently developed the Miller-Fisher syndrome (MFS). The product was separated into a water-insoluble gel of low Mr and a water-soluble component of high Mr. The structure of the core oligosaccharide region in LOSa is reported herein for comparison with LOSb from the C. jejuni O:10 reference strain, and is based on investigations carried out on: (1) O-deacylated LOSa; (2) the core oligosaccharide (OS 1a) liberated on acetic acid hydrolysis of the ketosidic linkages to lipid A, with accompanying loss of N-acetylneuraminic acid residues; (3) the product of the removal of phosphate residues from OS 1a 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 the core oligosaccharide region in LOSa from the MFS bacterial isolate had chains (1a), of which some were terminated by an N-acetylneuraminobiose [Neu5Ac(alpha 2-8)Neu5Ac] unit in a GD3 [Neu5Ac-Neu5Ac-Gal] epitope, and the inner regions of which were different from those of other C. jejuni serotypes. Similar experiments on LOSb from bacterial cells of the C. jejuni O:10 reference strain showed that the core oligosaccharide unit [1a, R = P (phosphoric monoester)] of LOSa from the MFS isolate was more uniformly complete than that of the O:10 reference strain [1b, R = AEP (2-aminoethylphosphate)] differing in the nature of the phosphate substituent at the inner heptose residue. The close structural 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-Barré syndrome (GBS) associated bacterium typed as C. jejuni O:19 in comparison with the lipo-oligosaccharide from the reference strain. Preliminary studies on the high Mr components showed that those from the O:10 strains were indistinguishable from each other, but were structurally unrelated to those from the GBS associated C. jejuni serotype O:19 isolates and the O:19 reference strain [G.O. Aspinall, A.G. McDonald, and H. Pang, Biochemistry, 33 (1994) 250-255].

Lipo-oligosaccharide of the Campylobacter lari type strain ATCC 35221. Structure of the liberated oligosaccharide and an associated extracellular polysaccharide

Lipo-oligosaccharide (LOS) from phenol-water extraction of cells of the Campylobacter lari type strain (ATCC 35221) was separated as a water-insoluble gel of low relative molecular mass (M(r)) from a water-soluble extracellular polysaccharide of high M(r). Structural investigations were performed on the liberated oligosaccharide and the extracellular polysaccharide, variously using 1H, 13C, and 31P NMR spectroscopy, linkage analysis, and fast atom bombardment-mass spectrometry of permethylated derivatives of the glycans and their products of chemical and enzymic degradation. The following structures are proposed for the highly branched region of the LOS: [formula: see text] and for the tetraglycosyl phosphate repeating unit of the extracellular polysaccharide: [-(PO3-)-->3)-beta-D-GlcpNAc-(1-->2)-6-d-alpha-L-gul-Hepp -(1-->2)-3-d-beta-D-threo-Penp-(1-->3)-6-d-alpha-L-gul-He pp-]n

Lipo-oligosaccharide of Campylobacter lari strain PC 637. Structure of the liberated oligosaccharide and an associated extracellular polysaccharide

Lipo-oligosaccharide from phenol-water extraction of cells of Campylobacter lari strain PC 637 was separated as a water-insoluble gel of low relative molecular mass (M(r)) from a water-soluble extracellular polysaccharide of high M(r). Structural investigations were performed on the lipo-oligosaccharide and the extracellular polysaccharide, variously using 1H, 13C, and 31P NMR spectroscopy, linkage analysis, and fast atom bombardment-mass spectrometry of permethylated derivatives of the glycans and their products of chemical and enzymic degradation. The following structures are proposed for the highly branched oligosaccharide region: [formula: see text] and for the tetraglycosyl phosphate repeating unit of the extracellular polysaccharide: [formula; see text]

Lipopolysaccharides from Campylobacter Jejuni Strains Associated with the Onset of the Guillain-Barré and Miller-Fisher Syndromes

The Miller-Fisher syndrome (MFS) is an infrequent variation of the more common neuropathy known as the Guillain-Barre syndrome (GBS). The onset of GBS is often preceded by intestinal infections with Campylobacter jejuni. Kuroki et al. 4 reported that 10 of their 14 cases of GBS were preceded by diarrhoea due to C. jejuni of serotype 0:19. In previous investigations LPS from two GBS-related isolates, OH4382 and OH4384 typed as C. jejuni O:19, were compared with that from the 0:19 serostrain1–3 The high Mr components were indistinguishable, with polysaccharide O chains consisting of disaccharide repeating units of an amidated hyaluronic acid. The core oligosaccharide (OS) regions in the O:19 se-rostrain consisted of molecules with terminal units that mimic human gangliosides GDla and GM1. The core OS regions of the OH4382 and OH4384 differed in structure, but contained a terminal trisaccharide epitope, Neu5Acα2→8Neu5Acα2→3Galβ, in mimicry of the human ganglioside GD3. We report here an examination of the LPS of a C. jejuni strain PG836 isolated from a patient with MFS at the Rhode Island Hospital, Providence, R.I., U.S.A. Serotyping and immunoblotting evidence revealed that the isolate was not of serotype O:19, but belonged to a different serotype (O:10).