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S G Wilkinson

Publications and source records attributed to S G Wilkinson.

At least 37 records · Page 2Linked to original sources
PubMed1996

Immunochemical characterization of two new O serotypes of Serratia marcescens (O27 and O28).

In an earlier study of the distribution of O-serotypes among clinical isolates of Serratia marcescens, two apparently new serotypes were identified, represented by strains S1254 and S3255. Studies using ELISA, immunoblotting and the Quellung reaction have shown that they qualify for inclusion in the O-antigenic typing scheme on three counts: (1) they possess chemically distinct O-antigenic repeating units, (2) the O-antigens are serologically distinguishable from all others, and (3) they are found in a significant proportion of clinical S. marcescens strains (13% and 6% respectively). S1254, the type strain for serotype O27, is an acapsular strain which expressed a glucorhamnan with a disaccharide repeating unit as its lipopolysaccharide side chain. It cross-reacts with serotype O4, the O antigen of which is an O-acetylated form of the O27 glucorhamnan, but this cross-reaction can be eliminated by reciprocal cross-absorption. S3255, the type strain for serotype O28, has a mannose homopolymer as its O-antigen and is the only S. marcescens serotype with a trimeric repeating-unit structure. However, it cross-reacts with the O5 serotype strain due to similarities in their acidic capsular polysaccharides. Cross-absorption and the production of serum to an acapsular variant of serotype strain O28 produced typing reagents which could differentiate serotypes O5 and O28.

Carbohydrate Sequence↗
PubMed1996

Structure of the O-specific polysaccharide of Acinetobacter baumannii O5 containing 2-acetamido-2-deoxy-D-galacturonic acid.

A polysaccharide containing 2-acetamido-2-deoxy-D-glucose (GlcNAc), 2-acetamido-2-deoxy-L-fucose (FucNAc), and 2-acetamido-2-deoxy-D-galacturonic acid (GalNAcA) was isolated from an aqueous phenol extract of lipid-free, isolated cell walls of the reference strain for Acinetobacter baumannii serogroup O5, by mild acid hydrolysis of the extract and chromatography of the water-soluble products on Sephadex G-50. By means of NMR studies, methylation analysis, carboxyl reduction and chemical degradations, the repeating unit of the polymer was identified as a branched tetrasaccharide of the structure shown. The serologically active polymer is believed to correspond to the side chain of the O5 lipopolysaccharide: [table: see text]

Acinetobacter↗
PubMed1996

Structural studies of the putative O-specific polysaccharide of Acinetobacter baumannii O11.

A major polysaccharide containing D-galactose, D-glucose and 2-acetamido-2-deoxy-D-galactose was obtained after mild acid hydrolysis of the water-soluble material released by treatment of cell walls from Acinetobacter baumannii strain O11 with hot, aqueous phenol. By means of NMR studies, Smith degradation and N-deacetylation/deamination, the repeating unit of the polymer was identified as a branched pentasaccharide of the structure shown. Also present was a minor polymer containing glucose, 2-acetamido-2-deoxyglucose-and 2-acetamido-2-deoxygalactose, the structure of which was not elucidated. On serological testing, the polymeric material was shown to correspond to the O-antigenic moiety of the parent extract (assumed to be lipopolysaccharide) and circumstantial evidence indicated that O11 specificity was conferred by the major polymer. [formula: see text]

Acinetobacter↗
PubMed1996

Structure of the O-specific polysaccharide from Burkholderia pickettii strain NCTC 11149.

A polymeric fraction (the putative O antigen) has been isolated from the lipopolysaccharide of the type strain of Burkholderia pickettii. The components of the polymer and their molar proportions were: L-rhamnose (3), 2-acetamido-2-deoxy-D-glucose (1), and O-acetyl (1). By means of NMR studies and chemical degradations, the basic repeating-unit of the polymer was identified as a linear tetrasaccharide of the structure shown. The O-acetyl group is probably located at position 2 of the 3-substituted alpha-L-Rha p. Similar polymers constitute O antigens in the related species Burkholderia solanacearum.

Acetylglucosamine↗
PubMed1996

Structure of the O3 antigen of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia.

The O antigen isolated from the lipopolysaccharide of a strain of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia serogroup O3 was found to contain 4-acetamido-4,6-dideoxy-D-galactose, D-fucose, and N-acetyl-D-glucosamine. By means of chemical degradations and NMR spectroscopy the repeating unit of the O-specific polymer was determined to be a branched trisaccharide repeating-unit of the structure shown.

Carbohydrate Conformation↗
PubMed1995

Structural studies of the putative O-specific polysaccharide of Acinetobacter baumannii O2 containing 3,6-dideoxy-3-N-(D-3-hydroxybutyryl)amino-D-galactose.

A polysaccharide containing D-galactose, 2-deoxy-2-N-acetylamino-D-galactose and 3,6-dideoxy-3-N-(D-3-hydroxybutyryl)amino-D-galactose, probably corresponding to the lipopolysaccharide side chain, was obtained from an aqueous phenol extract of isolated cell walls from Acinetobacter baumannii strain O2. By means of NMR studies and chemical degradations, the repeating unit of the polymer was identified as a branched hexasaccharide of the structure shown, where Fuc3N represents 3-amino-3,6-dideoxygalactose and R represents D-3-hydroxybutyryl. Serological tests indicated that the polymer corresponded to the O2 antigen.

Acinetobacter↗
PubMed1995

Structure of the O6 antigen of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia.

A polysaccharide containing D-xylose, L-rhamnose, and N-acetyl-D-glucosamine was released on mild acid hydrolysis of the lipopolysaccharide extracted from defatted cell walls of Stenotrophomonas (Xanthomonas or Pseudomonas) maltophilia strain 557, the reference strain for serotype O6. By means of NMR spectroscopy and chemical degradations, the repeating unit of the polymer was identified as a branched trisaccharide with the structure shown. [formula: see text]

Acetylglucosamine↗
PubMed1995

Characterization of a lipopolysaccharide O antigen containing two different trisaccharide repeating units from Burkholderia cepacia serotype E (O2).

The O antigen of the lipopolysaccharide of Burkholderia cepacia serotype E (O2) was shown by a combination of methylation analysis, partial hydrolysis, NMR, and mass spectrometric methods to be a high molecular weight polysaccharide composed of two different trisaccharide repeating units in the ratio 2:1. The major trisaccharide component is composed of two alpha-D-mannopyranosyl and one beta-D-galactopyranosyl residues with the structure, [-->2)-alpha-D-Man p-(1-->2)-alpha-D-Man p-(1-->4)-beta-D-Gal p-(1-->]n The minor trisaccharide component is a D-mannan composed of two alpha- and one beta-D-mannopyranosyl residues with the structure, [-->2)-alpha-D-Man p-(1-->2)-alpha-D-Man p-(1-->3)-beta-D-Man p-(1-->]n

Carbohydrate Conformation↗
PubMed1995

Structures of the two polymers present in the lipopolysaccharide of Burkholderia (Pseudomonas) cepacia serogroup O4.

Like several other strains of Burkholderia (Pseudomonas) cepacia, the reference strain for serogroup O4 in the French typing scheme [Heidt, A., Monteil, H. & Richard, C. (1983) J. Clin. Microbiol. 18, 738-740] produces a lipopolysaccharide containing two distinct polymers. Attempts to separate the polymers chromatographically were unsuccessful, but the periodate-resistant major polymer could be isolated by application of the Smith degradation technique to the mixture. By means of chemical and NMR spectroscopic analysis, the following structure could be assigned to the repeating unit of the major polymer: -->3)-alpha-D-Galp-(1-->3)-beta-D-Galp-(1-->3)-beta-D-GalpNAc-(1-->. The following structure of the repeating unit of the minor polymer was established from similar studies of its degradation product, resulting from the oxidation of L-rhamnose (Rha), and of the original mixture: -->3)-alpha-D-GalpNAc-(1-->3)-beta-D-GalpNAc-(1-->4)-alpha-L-Rhap- (1-->. Individually, the polymers have recently been found in related strains of B. cepacia. The minor polymer was identified as the O-antigen in serotype A of a Canadian typing scheme [Beynon, L. M. & Perry, M. B. (1993) Biochem. Cell Biol. 71, 417-420], and the major polymer in serotype C of a Japanese typing scheme [Paramonov, N. A., Shashkov, A. S., Knirel, Y. A., Soldatkina, M. A. & Zakharova, I. Y. (1994) Bioorg. Khim. 20, 984-993]. In the case of the O4 strain studied here, both polymers were produced under a variety of growth conditions.

Biopolymers↗
PubMed1995

Structural and serological studies of lipopolysaccharides from proposed new serotypes (O25 and O26) of Serratia marcescens.

The surface polysaccharides of the two most recently proposed O-serotype strains of Serratia marcescens, O25 and O26, were characterised in terms of their chemical structure and immunological reactions. No polymer was isolated from O25, which was shown to lack both capsular K-antigen and smooth, O-antigenic lipopolysaccharide. A neutral polysaccharide was isolated from O26 and shown to be a polymer of rhamnose and N-acetylgalactosamine of the type previously found in the O9 and O15 reference strains. Serological cross-reactions among all three strains were demonstrated by using both whole-cell enzyme-linked immunosorbent assay and immunoblotting of lipopolysaccharide resolved by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. No acidic polysaccharide was found in O26 and this was consistent with the absence of an immunogenic capsule. Thus, neither strain qualifies for inclusion as a new serotype in either an O-typing or a K-typing scheme.

Lipopolysaccharides↗
PubMed1995

Structure of an acidic microcapsular glycan from the reference strain (C.D.C. 866-57) for Serratia marcescens serogroup O1.

The structure of the acidic polysaccharide from Serratia marcescens serogroup O1 has been investigated. NMR spectroscopy together with sugar and methylation analysis have been used as well as a uronic degradation. The polysaccharide consists of pentasaccharide repeating units having the following structure. (sequence see text) The polysaccharide also contains one equivalent of O-acetyl groups per repeating unit present on, inter alia, a hydroxymethyl group.

Acetylglucosamine↗
PubMed1995

Structure of the O10 antigen of Stenotrophomonas (Xanthomonas) maltophilia.

A polysaccharide containing L-rhamnose and L-xylose was isolated from the lipopolysaccharide extracted from the cell walls of the reference strain for Stenotrophomonas (Xanthomonas) maltophilia serogroup O10. By means of NMR studies and methylation analysis, the repeating unit of the polymer was identified as a branched tetrasaccharide of the structure shown. [formula: see text]

Carbohydrate Sequence↗
PubMed1994

Structure of the putative O10 antigen from Acinetobacter baumannii.

A polysaccharide containing L-rhamnose, 2-acetamido-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-mannose was obtained from an aqueous phenol extract of isolated cell walls from the reference strain for Acinetobacter baumannii serogroup O10. By means of NMR studies and chemical degradations, the repeating unit of the polymer (the putative O10 antigen) was identified as a branched pentasaccharide of the structure shown.

Acinetobacter↗
PubMed1994

Structure of a surface polysaccharide from Acinetobacter baumannii strain 214.

A polysaccharide containing D-galactose, D-glucose, and 2-acetamido-2-deoxy-D-galactose was obtained from an aqueous phenol extract of isolated cell walls from Acinetobacter baumannii strain 214. By means of NMR studies and chemical degradations, the repeating unit of the polymer was identified as a branched trisaccharide of the structure shown. [formula: see text]

Acinetobacter↗
PubMed1994

Structure of the O9 antigen from Burkholderia (Pseudomonas) cepacia.

The O9 antigen of Burkholderia (Pseudomonas) cepacia has the following disaccharide repeating-unit: -->4)-alpha-D-Glcp-(1-->3)-alpha-L-Rhap-(1--> The same unit is present in the O antigens of Serratia marcescens strain S1254 and serogroup O4 (predominantly acetylated at O-2 of rhamnose in the latter case).

Burkholderia cepacia↗
PubMed1993

Structure of the O19 antigen of Xanthomonas maltophilia.

The O-specific polymer from a strain of Xanthomonas maltophilia O19 contains D-glucose, L-rhamnose, and D-fucose. By means of chemical degradations and NMR studies, the repeating unit of the polymer was determined to be a branched tetrasaccharide of the structure shown. [formula: see text]

Base Sequence↗
PubMed1993

Structural and serological characterisation of an O-specific polysaccharide from Serratia plymuthica.

The surface polysaccharides of a strain of Serratia plymuthica were characterised and shown to consist of a linear, acidic galactoglucomannan as well as a major and a minor neutral galactan. Immunoblotting results demonstrated cross-reactions between this strain and others with similar galactans (S. marcescens O16 and O20, Klebsiella O1, and Pasteurella haemolytica T4 and T10).

Antigens, Bacterial↗