tailieunhanh - Báo cáo Y học: The structures of the lipooligosaccharide and capsule polysaccharide of Campylobacter jejuni genome sequenced strain NCTC 11168

Campylobacter jejuniinfections are one of the leading causes of human gastroenteritis and are suspected of being a pre-cursor to Guillain–Barre´ and Miller–Fisher syndromes. Recently, the complete genome sequence ofC. jejuniNCTC 11168wasdescribed. In this study, themolecular structureof the lipooligosaccharide and capsular polysaccharide of C. jejuniNCTC 11168 was investigated. The lipooligosac-charide was shown to exhibit carbohydrate structures anal-ogous to the GM1a and GM2 carbohydrate epitopes of human gangliosides (shown below). | Eur. J. Biochem. 269 5119-5136 2002 FEBS 2002 doi The structures of the lipooligosaccharide and capsule polysaccharide of Campylobacterjejuni genome sequenced strain NCTC 11168 Frank St. Michael Christine M. Szymanski Jianjun Li Kenneth H. Chan Nam Huan Khieu Suzon Larocque Warren W. Wakarchuk Jean-Robert Brisson and Mario A. Monteiro Institute for Biological Sciences National Research Council of Canada Ottawa Canada Campylobacter jejuni infections are one of the leading causes of human gastroenteritis and are suspected of being a precursor to Guillain-Barre and Miller-Fisher syndromes. Recently the complete genome sequence of C. jejuni NCTC 11168 was described. In this study the molecular structure of the lipooligosaccharide and capsular polysaccharide of C. jejuni NCTC 11168 was investigated. The lipooligosac-charide was shown to exhibit carbohydrate structures analogous to the GM1a and GM2 carbohydrate epitopes of human gangliosides shown below 6-O-Me-D-a-L-glcHepp 1 fl 3 fi2 -P-D-Ribf- 1-5 -P-D-Galf NAc- 1-4 -a-D-GlcpA6 NGro - 1fi The structural information presented here will aid in the identification and characterization of specific enzymes that are involved in the biosynthesis of these structures and may P PEtn GM1a GM2 fl 6 b-Gal- 1fi3 - b-D-GalNAc- 1 fi4 - b-D-Gal- 1 fi3 -b-D-Gal- 1fi3 -L a-D-Hep- 1fi3 -L a-D-Hep- 1 fi5 Kdo 3 2 2 4 fl fl fl fl 2 1 1 1 y a-Neu5Ac y a-D-Gal b-D-Glc b-D-Glc The high Mr capsule polysaccharide was composed of b-D-Ribp b-D-GalfNAc a-D-GlcpA6 NGro a uronic acid amidated with 2-amino-2-deoxyglycerol at C-6 and 6-O-methyl-D-glycero-a-L-gluco-heptopyranose as a sidebranch shown below lead to the discovery of potential therapeutic targets. In addition the correlation of carbohydrate structure with gene complement will aid in the elucidation of the role of these surface carbohydrates in C. jejuni pathogenesis. Keywords lipooligosaccharide capsule electron spray ionization mass spectrometry .