Structure of the Oligosaccharide Chain of the SR-Type Lipopolysaccharide of Ralstonia solanacearum Toudk-2

Abstract

Aiming at improving classification and taxonomy of Gram-negative phytopathogenic bacteria, we studied the structure of the lipopolysaccharide of Ralstonia solanacearum. Mild acid hydrolysis of the lipopolysaccharide of strain Toudk-2 followed by gel chromatography resulted in an O-polysaccharide and two oligosaccharide fractions. The smallest-size oligosaccharide fraction was studied by sugar analysis, high-resolution electrospray ionization mass spectrometry, and, after fractionation by anion-exchange chromatography on HiTrap Q, by one- and two-dimensional (1)H and (13)C NMR spectroscopy. It was found that the isolated oligosaccharides consist of the lipopolysaccharide core with one O-polysaccharide repeat (O-unit) attached. The core exists in two major glycoforms differing from each other in a lateral octulosonic acid residue, which is either D-glycero-D-talo-oct-2-ulosonic acid or 3-deoxy-D-manno-oct-2-ulosonic acid. A peculiar feature of the core is the occurrence of 4-amino-4-deoxy-L-arabinose nonstoichiometrically linked to a heptose residue. The full structures of the core and the biological O-unit as well as the site of the attachment of the O-unit to the core were established.

Identification of a Bifunctional UDP-4-keto-pentose/UDP-xylose Synthase in the Plant Pathogenic Bacterium Ralstonia solanacearum Strain GMI1000, a Distinct Member of the 4,6-Dehydratase and Decarboxylase Family

“…GMI1000. The lower catalytic efficiency of the enzyme to form UDP-xylose from UDP-4-keto-pentose is consistent with the lower level of xylosyl residues found on Ralstonia LPS, when compared with the 4-amino-4-deoxy-L-arabinose (L-Ara4N) residues (33).…”

“…residue of the core oligosaccharide (33), as well as a trace amount of a xylosyl residue linked to a rhamnose of the O-polysaccharide (33-35) (supplemental Fig. S3A).…”

Aminoarabinose is essential for lipopolysaccharide export and intrinsic antimicrobial peptide resistance in Burkholderia cenocepacia†

“…Additionally, in B. cenocepacia and other Burkholderia species (Gronow et al ., 2003; Isshiki et al ., 2003; Silipo et al ., 2005; 2007; De Soyza et al ., 2008; Ortega et al ., 2009), as well as in some strains of Serratia marcescens (Vinogradov et al ., 2006), l ‐Ara4N is added to both the lipid A and at position 8 of a branched d ‐ glycero ‐ d ‐ talo ‐oct‐2‐ulosonic acid (Ko) inner core OS residue. In contrast, in most other Gram‐negative bacteria l ‐Ara4N is added only to lipid A with the exception of Proteus strains (Boll et al ., 1994; Kondakova et al ., 2005) and Ralstonia solanacearum (Zdorovenko et al ., 2008), which can additionally attach l ‐Ara4N to 3‐deoxy‐ d ‐ manno ‐oct‐2‐ulosonic acid (Kdo), and l ‐glycero‐ d ‐ manno ‐heptose (Hep) residues of the core OS respectively.…”

Adsorption Sequencing as a Rapid Method to Link Environmental Bacteriophages to Hosts

“…These phages might interact with a surface element that is common to all these hosts. This hypothesis is reinforced by the fact that Ralstonia were long assigned to the genus Pseudomonas within the γ-proteobacteria, despite differences in membrane composition ( Yabuuchi et al., 1995 ) and lipopolysaccharide structure ( Zdorovenko et al., 2008 ). Alternatively, in similar fashion to Enterobacteria phage phi92 ( Schwarzer et al., 2012 ), they may harbor multiple receptor-adsorbing proteins in their large genomes.…”