tailieunhanh - Báo cáo khoa học: The structure of the carbohydrate backbone of the lipopolysaccharide from Acinetobacter baumannii strain ATCC 19606

The chemical structure of the phosphorylated carbohydrate backbone of the lipopolysaccharide (LPS) fromAcineto-bacter baumanniistrain ATCC 19606 was investigated by chemical analysis and NMR spectroscopy of oligosaccha-rides obtained after deacylation or mild acid hydrolysis. Fromthe combined information the following carbohydrate backbones can be deduced | Eur. J. Biochem. 269 422-430 2002 FEBS 2002 The structure of the carbohydrate backbone of the lipopolysaccharide from Acinetobacterbaumannii strain ATCC 19606 Evgeny V. Vinogradov1 Jens 0. Duus1 Helmut Brade2 and Otto Holst2 department of Chemistry Carlsberg Laboratory Valby Copenhagen Denmark division of Medical and Biochemical Microbiology Research Center Borstel Borstel Germany The chemical structure of the phosphorylated carbohydrate backbone of the lipopolysaccharide LPS from Acineto-bacter baumannii strain ATCC 19606 was investigated by chemical analysis and NMR spectroscopy of oligosaccharides obtained after deacylation or mild acid hydrolysis. From the combined information the following carbohydrate backbones can be deduced a-Gal NR1 P-GlqpN a-Kdo 1 1 2 ị ị 4 7 4 where R1 HandR2 a-Glcp- 1 2 -b-Glcp- 1 4 -p-Glcp- 1 4 -b-Glcp- 1 as major and R1 Ac and R2 H as minor products. All monosaccharides are D-confgured. Also smaller oligosaccharide phosphates were identified that are thought to represent degradation products of the above structures. Keywords Acinetobacter baumannii lipopolysaccharide core region structural analysis NMR spectroscopy. R2- 3 -a-GlcpNAcA- 1- 4 -a-Kdo- 2- 5 -a-Kdo- 2- 6 -P-GlcpN4P- 1- 6 The Gram-negative bacterium Acinetobacter Moraxella-ceae is isolated from soil and water which represent its natural habitats. However the genus has gained increasing importance as a causative agent of nosocomial infections . bacteremia secondary meningitis in recent years 1 . As in other Gram-negative bacteria Acinetobacter possesses lipopolysaccharides LPS in the outer membrane of the cell wall that have been shown to represent useful chemotaxonomic and antigenic markers for its identification and differentiation. The occurrence of S-form LPS in Acinetobacter has unequivocally been proven recently and the structures of a number of O-specifc polysaccharides and their antigenic characterization have been published 2-9 . The core region of .