Structure of the K141 capsular polysaccharide produced by Acinetobacter baumannii isolate KZ1106 that carries KL141 at the chromosomal K locus.

The structure of the K141 type capsular polysaccharide (CPS) produced by Acinetobacter baumannii KZ1106, a clinical isolate recovered from Kazakhstan in 2016, was established by sugar analyses and one- and two-dimensional H and C NMR spectroscopy. The CPS was shown to consist of branched tetrasaccharide repeating units (K-units) with the following structure: This structure was found to be consistent with the genetic content of the KL141 CPS biosynthesis gene cluster at the chromosomal K locus in the KZ1106 whole genome sequence. Assignment of the encoded enzymes allowed the first sugar of the K unit to be identified, which revealed that the β-d-GlcpNAc-(1→3)-d-GlcpNAc bond is the linkage between K-units formed by the Wzy polymerase.

New Phages Brutus and Scipio: Biology, Evolution, and Phage-Host Interaction.

Two novel virulent phages of the genus infecting , a significant nosocomial pathogen, have been isolated and studied. Phages Brutus and Scipio were able to infect strains belonging to the K116 and K82 capsular types, respectively. The biological properties and genomic organization of the phages were characterized.

Revised structure of the polysaccharide from Acinetobacter baumannii LUH5551 assigned as the K63 type capsular polysaccharide.

K63 capsular polysaccharide produced by Acinetobacter baumannii isolate LUH5551 (previously designated isolate O24) was re-examined using sugar analysis, Smith degradation, and one- and two-dimensional H and C NMR spectroscopy. Though previously reported as O24 consisting of linear tetrasaccharide units that include a 7-acetamido-5-acylamino form of 8-epilegionaminic acid [8eLeg5R7Ac, acylated at C5 with (S)-3-hydroxybutanoyl or acetyl (1:1)], the elucidated structure of the K63 type capsule was found to include a derivative of 5,7-diamino-3,5,7,9-tetradeoxy-d-glycero-d-galacto-non-2-ulosonic (legionaminic) acid, Leg5Ac7R, where R is either (S)-3-hydroxybutanoyl or an acetyl group (∼1:1 ratio). This finding is consistent with the presence of the lgaABCHIFG gene module for Leg5Ac7R biosynthesis in the KL63 gene cluster at the capsular polysaccharide (CPS) biosynthesis K locus in the LUH5551 genome.

The K70 and K9 capsular polysaccharides consist of related K-units linked by the same Wzy polymerase and cleaved by the same phage depolymerases.

Bacteriophage show promise for the treatment of infections that resist all therapeutically suitable antibiotics. Many tail-spike depolymerases encoded by phage that are able to degrade capsular polysaccharide (CPS) exhibit specificity for the linkage present between K-units that make up CPS polymers. This linkage is formed by a specific Wzy polymerase, and the ability to predict this linkage using sequence-based methods that identify the Wzy at the K locus could assist with the selection of phage for therapy.

A highly branched novel galactofuranan in the cell wall of Clavibacter tesselarius VKM Ac-1406.

The structures of two cell wall glycopolymers were studied in the plant pathogenic bacterium Clavibacter tesselarius VKM Ac-1406 (family Microbacteriaceae, order Micrococcales, class Actinomycetes). The predominant polymer was a novel (1 → 6)-linked β-d-galactofuranan with a highly branched repeating unit, α-L-Rhap-(1 → 3)-α-D-Galp-(1 → 2)-[α-L-Rhap-(1 → 3)]-α-D-Fucp-(1 →, at O-2 on every second galactofuranose residue. The second polymer present in small amounts was acidic with the repeating unit, →3)-α-D-Galp-(1 → 3)-α-D-[4,6-S-Pyr]-Manp-(1 → 3)-α-D-Manp-[2OAc]-(1→, and was reported in all Clavibacter species investigated to date.

A novel cell wall galactofuranan in Clavibacter phaseoli VKM Ac-2641.

A glycopolymer of novel structure was found in the cell wall of plant pathogen Clavibacter phaseoli VKM Ac-2641 (family Microbacteriaceae, class Actinomycetes). The glycopolymer was (1 → 6)-linked β-d-galactofuranan with side branched trisaccharide, α-D-Manp-(1 → 2)-[α-D-Manp-(1 → 3)]-α-D-Ribf-(1→ at O-2 on every second galactofuranose residue. The galactofuranan structure was established by chemical and NMR spectroscopic methods using one- and two-dimensional techniques H,H COSY, TOCSY, ROESY and H,C HSQC, HMBC.

Structural and genetic relatedness of the O-antigens of Escherichia coli O50 and O2.

An O-specific polysaccharide (O-antigen) was isolated by mild acid degradation of the lipopolysaccharide of Escherichia coli O50 followed by gel chromatography on Sephadex G-50. The following structure of the tetrasaccharide repeat was established by sugar analysis and 1D and 2D H and C NMR spectroscopy: →3)-α-l-Rhap-(1 → 2)-α-l-Rhap-(1 → 3)-β-l-Rhap-(1 → 4)-β-d-GlcpNAc-(1→ The linear O50 polysaccharide has the same structure as the main chain of the branched O polysaccharide of E. coli O2 studied earlier [Jansson et al.

Serological classification and epitope specificity of Proteus vulgaris TG 251 from Proteus serogroup O65.

Introduction: Proteus rods are currently subdivided into five named species, i.e. Proteus mirabilis, P.