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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The neutral fraction (neutral CPS-K) of Klebsiella pneumoniae capsular polysaccharide (CPS-K) from type 1, Kasuya strain, has already been reported as the active substance responsible for the strong adjuvant effect of CPS-K. The present results demonstrate that neutral CPS-K exhibits further common biological activities with lipopolysaccharide (LPS) isolated from Salmonella enteritidis. The intensity of the lethality in mice of neutral CPS-K by the intraperitoneal route is very similar to that of LPS. Its lethality for mice by the intravenous (i.v.) route is significantly stronger than that of LPS, because the degree of increase in the sensitivity to their lethality by i.v. challenge is smaller for LPS than for neutral CPS-K. The intensity of the pyrogenicity of neutral CPS-K in rabbits is approximately one-tenth of that of LPS as judged by the minimal pyrogenic doses and fever indices. The skin-preparatory potency of neutral CPS-K for the dermal Shwartzman phenomenon in rabbits is also approximately one-tenth of that of LPS compared on the basis of the minimal skin-preparatory doses. When injected i.v., neutral CPS-K exhibits a provocative effect on hemorrhagic reactions in skin sites prepared with neutral CPS-K or LPS.
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PMID:Adjuvant action of capsular polysaccharide of Klebsiella pneumoniae on antibody response. V. Further biological properties of the active substance. 78 3

Two mutants which lacked both capsular and lipopolysaccharide O-antigen polysaccharides were isolated from Klebsiella aerogenes serotype 2 by phage selection; these were designated rough mutants. The polysaccharide fractions solubilized by partial acid hydrolysis of the lipopolysaccharide from both the wild type and mutants were chromatographed on Sephadex G-50. Analysis of the fractions obtained confirmed that the rough mutants lacked the galactan portion of the molecule, which is analogous to the Salmonella O-antigen polysaccharide. Membranes prepared from wild-type K. aerogenes, from a non-mucoid strain (lacking capsule only), and from one of the rough mutants were used in incubation mixtures to compare the biosynthesis of polysaccharides by these organisms. The incorporation of sugar nucleotides into both lipid intermediates and polymer was followed. Results show that the transferases were apparently present in all membranes, while the polymerases were absent in both the non-mucoid and rough mutants.
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PMID:Isolation of rough mutants of Klebsiella aerogenes and their synthesis of polysaccharides. 78 14

Exopolysaccharides interfere with the isolation and characterization of plasmid DNA from gram-negative bacteria. To repress capsular polysaccharide production, bacteria were cultured in medium containing bismuth nitrate and sodium salicylate. Rapid removal of other contaminating bacterial surface components was achieved by mild acidic zwitterionic detergent extraction. After treatment, bacterial cells were more readily lysed in alkaline detergents. The resulting plasmid preparations contained virtually no capsular polysaccharide and relatively small quantities of lipopolysaccharide and protein, yet they produced yields of nucleic acids similar to those of conventional plasmid preparations. Conventional preparations from encapsulated organisms were largely insoluble and appeared as smears following agarose gel electrophoresis, with indefinite plasmid banding. Plasmids prepared by the new method were highly soluble in conventional buffers and exhibited high-resolution plasmid banding patterns in agarose gels. Plasmids as large as 180 kbp could be isolated and visualized, without apparent nicking, and were readily digested by restriction endonuclease enzymes. The method proved effective with encapsulated or mucoid strains of Klebsiella pneumoniae, Escherichia coli, Acinetobacter anitratus, Salmonella typhimurium, and Enterobacter species. The complete method for plasmid isolation was not suitable for Pseudomonas aeruginosa because of the inhibitory effects of bismuth. Thus, removal of contaminating bacterial surface structures enabled the rapid isolation and characterization of plasmids from mucoid clinical isolates, without the use of organic solvents, CsCl gradients, or expensive, disposable columns.
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PMID:Rapid plasmid DNA isolation from mucoid gram-negative bacteria. 133 82

Previous chemical analyses identified two structurally distinct O polysaccharides in the lipopolysaccharide of Klebsiella pneumoniae serotype O1:K20 (C. Whitfield, J. C. Richards, M. B. Perry, B. R. Clarke, and L. L. MacLean, J. Bacteriol. 173:1420-1431, 1991). The polysaccharides were designated D-galactan I and D-galactan II; both are homopolymers of galactose. To begin investigation of the synthesis and expression of these O polysaccharides, we have cloned a 7.3-kb region of the chromosome of K. pneumoniae O1:K20, containing the his-linked rfbkpO1 (O-antigen biosynthesis) gene cluster. In Escherichia coli K-12 and Salmonella typhimurium, rfbkpO1 directed the synthesis of D-galactan I but not D-galactan II. The cloned rfbkpO1 genes did not complement a mutation affecting D-galactan II synthesis in K. pneumoniae CWK37, suggesting that another (unlinked) locus is also required for D-galactan II expression. However, plasmids carrying rfbkpO1 did complement a mutation in K. pneumoniae CWK43 which eliminated expression of both D-galactan I and D-galactan II, indicating that at least one function is common to synthesis of both polymers. Synthesis of D-galactan I was dependent on chromosomal galE and rfe genes. Hybridization experiments indicated that the rfbkpO1 sequences from different serotype O1 Klebsiella isolates showed some restriction fragment length polymorphism.
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PMID:Molecular cloning of the rfb region of Klebsiella pneumoniae serotype O1:K20: the rfb gene cluster is responsible for synthesis of the D-galactan I O polysaccharide. 137 55

The lipopolysaccharide (LPS) of Klebsiella serotype O2 is antigenically heterogeneous; some strains express multiple antigenic factors. To study this heterogeneity, we determined the structure of the O-antigen polysaccharides in isolates belonging to serotypes O2(2a), O2(2a,2b), and O2(2a,2c), by using composition analysis, methylation analysis, and both 1H and 13C nuclear magnetic resonance spectroscopy. The repeating unit structure of the 2a polysaccharide was identified as the disaccharide [----3)-beta-D-Galf-(1----3)-alpha-D-Galp-(1----] and was identical to D-galactan I, one of two O polysaccharides present in the LPS of Klebsiella pneumoniae serotype O1 (C. Whitfield, J. C. Richards, M. B. Perry, B. R. Clarke, and L. L. MacLean, J. Bacteriol. 173:1420-1431, 1991). LPS from serotype O2(2a,2b) also contained D-galactan I as the only O polysaccharide, suggesting that the 2b antigen is not an O antigen. The LPS of serotype O2(2a,2c) contained a mixture of two structurally distinct O polysaccharides and provides a second example of this phenomenon in Klebsiella spp. One polymer was identical to D-galactan I, and the other polysaccharide, the 2c antigen, was a polymer with a disaccharide repeating unit structure, [----3)-beta-D-GlcpNAc-(1----5)-beta-D-Galf-(1----]. The 2c structure does not resemble previously reported O polysaccharides from Klebsiella spp. Periodate oxidation confirmed that D-galactan I and the 2c polysaccharide are distinct glycans, rather than representing domains within a single polysaccharide chain. Monoclonal antibodies against the 2c antigen indicated that only LPS molecules with the longest O-polysaccharide chains contained the 2c epitope.
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PMID:Structural analysis of the O-antigen side chain polysaccharides in the lipopolysaccharides of Klebsiella serotypes O2(2a), O2(2a,2b), and O2(2a,2c). 137 28

The murine monoclonal IgM antibody E5 has been shown to significantly reduce the mortality and morbidity of patients with Gram-negative sepsis in a multicenter randomized placebo-controlled clinical trial. The in vitro binding characteristics of monoclonal antibody (mAb) E5 were studied using highly purified smooth lipopolysaccharide (LPS) isolated from a variety of clinically relevant, wild-type Gram-negative bacteria. Using a sensitive antibody-capture assay which involves immobilized mAb E5 and a chromogenic Limulus amebocyte lysate (LAL) LPS-detection system, mAb E5 was shown to bind to all 15 smooth LPS preparations tested, including LPS isolated from Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia and Yersinia species. When LPS was fractionated according to size by size-exclusion chromatography, mAb E5 was shown to bind to smooth LPS molecules that have long as well as short O-polysaccharide chains. These results confirm and extend those reported previously and demonstrate that the anti-lipid A mAb E5 binds specifically to a diverse spectrum of smooth LPS isolated from wild-type Gram-negative bacteria.
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PMID:Reactivity of monoclonal antibody E5 with endotoxin. II. Binding to short- and long-chain smooth lipopolysaccharides. 138 82

The adjuvant action of various lipopolysaccharides on immune responses to syngeneic tissue extract in mice was examined. Only lipopolysaccharides possessing the linear mannose homopolysaccharides as O-specific polysaccharides exhibited definite adjuvant action on immune responses to the autoantigens. The intensity of this adjuvant activity of lipopolysaccharide from Klebsiella O3 seemed to be the strongest.
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PMID:Novel adjuvant action of lipopolysaccharides that possess mannose homopolysaccharides as O-specific polysaccharides on immune responses to nonimmunogenic autoantigens in mice. 138 60

In this study, role of capsular polysaccharide (CPS) and lipopolysaccharide (LPS) of Klebsiella pneumoniae was investigated in experimental mice pneumonia model. Inoculation with K. pneumoniae mucoid strain DT-S into mice lung induced expansive, voluminous lethal pneumonia characterized with thickening of the alveolar septa caused by infiltration of inflammatory cell and packing of bacteria within alveolar spaces. On the other hand, mice lung inoculated with K. pneumoniae DT-X, which was non-mucoid mutant isolated from DT-S during natural passage, showed infiltration of inflammatory cell into alveolar spaces but there was no death of mice during the course of this pneumonia. Inoculation of CPS 100 micrograms of DT-S strain into mice lung induced lesser extent of accumulation of inflammatory cell than that of LPS 4 micrograms of this strain. Stimulation of alveolar and peritoneal macrophage with CPS, even at a concentration of 100 micrograms/ml, induced weaker Interleukin-1 (IL-1) activity than stimulation with LPS 4 micrograms/ml. These results suggest that since CPS of K. pneumoniae DT-S encapsulate bacteria including LPS, CPS may inhibit chemotaxis of inflammatory cell and IL-1 production of macrophage to be induced by LPS during course of pneumonia. It is speculated that existence of CPS have important role in modulating host response to bacterial LPS, and this effect of CPS may be related with difference of pathological findings of lung and lethality between K. pneumoniae DT-S and DT-X.
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PMID:[Role of capsular polysaccharide and lipopolysaccharide of Klebsiella pneumoniae in experimental mice pneumonia model]. 140 9

Rat defensins were purified and tested for in vitro bactericidal assay against gram-positive and gram-negative bacteria. Staphylococcus aureus (209P, Cowan I, Smith diffuse and Smith compact) were resistant to defensins, whereas Staphylococcus epidermidis, Staphylococcus saprophyticus, Micrococcus lysodeikticus and Bacillus subtilis were less sensitive. Gram-negative bacteria, such as Pseudomonas aeruginosa (mucoid and K) and Klebsiella pneumoniae (Chedid, 277, and 8N3 which were heavily capsulated, moderately capsulated and noncapsulated, respectively) were all very sensitive to defensins and killed within 20 min. Escherichia coli was moderately sensitive and the rough mutants of lipopolysaccharide (LPS) of Salmonella typhimurium LT2, such as Ra, Rc, Rd, and Re were equally sensitive to defensins, being killed within 40 min. Lysozyme did not show any bactericidal activity except against M. lysodeikticus and B. subtilis, whereas it enhanced the bactericidal activity of defensins against P. aeruginosa, E. coli, and K. pneumoniae and suppressed the killing activity of defensins against S. typhimurium and S. aureus. With regard to the three synthetic rabbit defensins, NP1, NP4, and NP5, NP1 showed strong bactericidal activity against K. pneumoniae 277, comparable to that of rat defensins. Neither NP4 nor NP5 showed any bactericidal activity, while NP5 rather enhanced the bactericidal activity of NP1 against K. pneumoniae 277.
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PMID:Bactericidal activities of rat defensins and synthetic rabbit defensins on Staphylococci, Klebsiella pneumoniae (Chedid, 277, and 8N3), Pseudomonas aeruginosa (mucoid and nonmucoid strains), Salmonella typhimurium (Ra, Rc, Rd, and Re of LPS mutants) and Escherichia coli. 140 65

The stimulating activity of several preparations isolated from a membrane proteoglycan of a nonencapsulated smooth strain of Klebsiella pneumoniae (Kp-MPG) on the oxidative burst of human blood monocytes was assessed by luminol-enhanced chemiluminescence (CL). Five Kp derivatives were studied: a 34-kd acylpoly(1,3)galactoside (APG), obtained by drastic alkaline hydrolysis and purified by chromatography; an APG preparation subjected to acid hydrolysis that removed the core part and all fatty acids, leaving intact the galactose chain of APG (GC-APG); an APG preparation subjected to mild oxidation (ox APG); a preparation obtained by mild alkaline hydrolysis of Kp-MPG, containing additional ester-linked C14 and C16 fatty acids bound to the APG molecule (EFA-APG); and a polymer of the latter compound, APG pol. EFA-APG directly stimulated monocyte CL, whereas Kp-MPG, APG pol, and the whole bacterial cells had little or no activity. APG itself and ox APG induced a weaker response than EFA-APG. Polymyxin B sulfate completely inhibited the CL response to bacterial lipopolysaccharide (LPS) but not to EFA-APG. The stimulating action of EFA-APG on blood monocytes was dependent on the extracellular levels of both calcium and magnesium. Preincubation of monocytes with monoclonal antibody anti-Mac-1 directed against CD11b, the alpha chain of complement receptor type 3 (CR3; CD11b/CD18), strongly inhibited CL activation by EFA-APG and to a lesser extent CL activation by unopsonized zymosan and rough LPS. Altogether, these findings provide indirect evidence for the contribution of the CD11b/CD18 integrin in the functional interaction of EFA-APG with monocyte membranes. They demonstrate the role of fatty acids in the triggering of monocyte oxidative burst, while the polysaccharide chain itself does not contribute to induction of the CL response in this model. In keeping with the effects of EFA-APG and APG, we show that the monocyte CL response was triggered by bacterial LPS from the rough strain of Salmonella minnesota Re 595 and its lipid A, but not by LPS from smooth strains, again suggesting a critical role for the lipid moiety.
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PMID:Activation of human monocyte chemiluminescence response by acylpoly(1,3)galactosides derived from Klebsiella pneumoniae. 143 64


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