Dataset Information

Structure of the Lipopolysaccharide from the Bradyrhizobium sp. ORS285 rfaL Mutant Strain.

ABSTRACT: The importance of the outer membrane and of its main constituent, lipopolysaccharide, in the symbiosis between rhizobia and leguminous host plants has been well studied. Here, the first complete structural characterization of the entire lipopolysaccharide from an O-chain-deficient Bradyrhizobium ORS285 rfaL mutant is achieved by a combination of chemical analysis, NMR spectroscopy, MALDI MS and MS/MS. The lipid A structure is shown to be consistent with previously reported Bradyrhizobium lipid A, that is, a heterogeneous blend of penta- to hepta-acylated species carrying a nonstoichiometric hopanoid unit and possessing very-long-chain fatty acids ranging from 26:0(25-OH) to 32:0(31-OH). The structure of the core oligosaccharide region, fully characterized for the first time here, is revealed to be a nonphosphorylated linear chain with methylated sugar residues, with a heptose residue exclusively present in the outer core region, and with the presence of two singly substituted 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) residues, one of which is located in the outer core region. The lipid A moiety is linked to the core moiety through an uncommon 4-substituted Kdo unit.

SUBMITTER: Di Lorenzo F

PROVIDER: S-EPMC5542761 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Structure of the Lipopolysaccharide from the Bradyrhizobium sp. ORS285 rfaL Mutant Strain.

Di Lorenzo Flaviana F Palmigiano Angelo A Duda Katarzyna A KA Pallach Mateusz M Busset Nicolas N Sturiale Luisa L Giraud Eric E Garozzo Domenico D Molinaro Antonio A Silipo Alba A

ChemistryOpen 20170612 4

The importance of the outer membrane and of its main constituent, lipopolysaccharide, in the symbiosis between rhizobia and leguminous host plants has been well studied. Here, the first complete structural characterization of the entire lipopolysaccharide from an O-chain-deficient Bradyrhizobium ORS285 rfaL mutant is achieved by a combination of chemical analysis, NMR spectroscopy, MALDI MS and MS/MS. The lipid A structure is shown to be consistent with previously reported Brady ...[more]

PMID: 28794950

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Dataset Information

Structure of the Lipopolysaccharide from the Bradyrhizobium sp. ORS285 rfaL Mutant Strain.

Publications

Structure of the Lipopolysaccharide from the <i>Bradyrhizobium</i> sp. ORS285 <i>rfaL</i> Mutant Strain.

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