Ionizing groups in lipopolysaccharides of Pseudomonas cepacia in relation to antibiotic resistance.
Contrary to previous reports, lipopolysaccharides from Pseudomonas cepacia contain a 3-deoxyoct-2-ulosonic acid (probably a single residue). The lipopolysaccharides contain only two phosphate residues, one of which apparently forms a phosphodiester bridge between 4-amino-4-deoxyarabinose and a glucosamine residue in lipid A. The second, unlocated phosphate residue occurs mainly as a monoester in some lipopolysaccharides, and mainly as a diester in others. All lipopolysaccharides lack pyrophosphate residues. The results support the view that the resistance of P. cepacia to cationic antibiotics stems from ineffective binding to the outer membrane, as a consequence of the low number of phosphate and carboxylate groups in the lipopolysaccharide, and the presence of the protonated aminodeoxypentose.
Cox
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AD
School of Chemistry, University of Hull, UK.
Wilkinson
S G
SG
D000606:Amino Sugars; D000900:Anti-Bacterial Agents / Q000378:metabolism; D002240:Carbohydrate Sequence; D002412:Cations; D004352:Drug Resistance, Microbial; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010710:Phosphates / Q000032:analysis; D011549:Pseudomonas / Q000032:analysis / Q000187:drug effects* / Q000378:metabolism; D013400:Sugar Acids / Q000032:analysis
D000606:Amino Sugars; D000900:Anti-Bacterial Agents; D002412:Cations; D008070:Lipopolysaccharides; D010710:Phosphates; D013400:Sugar Acids; C002532:2-keto-3-deoxyoctonate; C040134:4-amino-4-deoxyarabinose