title: O-chain structure from the lipopolysaccharide of the human pathogen Halomonas stevensii strain S18214.
abstract: Halomonas stevensii is a Gram-negative, pathogenic, moderately halophilic bacterium isolated from the blood of a renal care patient. It optimally grows at 30-35°C at pH 8-9 and at a sea salt concentration ranging from 3.0% to 7.5%. Gram-negative bacterial infections are closely associated with the presence of the lipopolysaccharides (LPSs) on the outer membrane. These molecules consist of three regions covalently linked: the glycolipid (lipid A), the oligosaccharide region (core region), and the O-specific polysaccharide (O-chain, O-antigen). O-antigen seems to play an important role in the colonization step (adherence) and the ability to bypass host defense mechanisms. For this reason the structure elucidation of the O-chain repeating unit is important to improve knowledge about the role of LPS in the host-pathogen interaction. In this paper, we report the complete structure of the O-chain from the LPS of H. stevensii. The bacterial cells were cultivated and LPS was extracted by the PCP (phenol-chloroform-petroleum ether) method. After mild acid hydrolysis, the lipid A was removed by centrifugation and the obtained polysaccharide was analyzed by means of chemical analysis and one- and two-dimensional NMR spectroscopy giving the following structure:
authors.affiliation: Dipartimento di Chimica Organica e Biochimica, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Pieretti
authors.forename: Sara
authors.initials: S
authors.lastname: Carillo
authors.forename: Kwang Kyu
authors.initials: KK
authors.lastname: Kim
authors.forename: Keun Chul
authors.initials: KC
authors.lastname: Lee
authors.forename: Jung-Sook
authors.initials: JS
authors.lastname: Lee
authors.forename: Rosa
authors.initials: R
authors.lastname: Lanzetta
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Parrilli
authors.forename: M Michela
authors.initials: MM
authors.lastname: Corsaro
mesh_terms: D002240:Carbohydrate Sequence; D020632:Halomonas / Q000276:immunology*; D006801:Humans; D008969:Molecular Sequence Data; D019081:O Antigens / Q000737:chemistry* / Q000276:immunology
chemical_list: D019081:O Antigens