Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunochemical analysis of 2 polysaccharide-containing structures of the lypopolysaccharide of the plague causative agent (main somatic antigen and lipopolysaccharide) isolated from K-1 strain and a number of its antibiotic resistant mutants was carried out. It was shown that development of resistance to streptomycin alone or its combination with monomycin did not cause detectable changes in the monosaccharide composition and serological properties of the cultures tested. More significant changes associated with development of complex resistance, i.e. K-1 (Strr leads to Penr leads to Tetr) were accompanied by a decrease in the content of hexozamine and serological activity of the main somatic antigen determining the O-specificity of the lipopolysaccharide. Defective changes in the monosaccharide composition and serological properties of both the main somatic antigen and the polysaccharide were observed in the yellow variant of the streptomycin resistant mutant K-1.
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PMID:[Characteristics of the polysaccharide-containing somatic antigens isolated from the K-1 strain of the plague microbe and its antibiotic-resistant variants]. 70 3

The effect of antibiotics such as amikacin, rifampicin, doxycycline, polymyxin B and cefotaxime on the toxins of the plague microbe (lipopolysaccharide + fraction II according to Beiker) was studied in vitro and in vivo. The study on the antibiotic neutralization of plague toxins revealed that only polymyxin had toxin neutralizing capacity which depended on the dose. Investigation of the polymyxin effect at various stages of plague infection showed that when polymyxin in a dose of 1250 units and a mixture of plague toxins in lethal doses were administered simultaneously to albino mice, the positive effect amounted to 100 per cent. When the antibiotic was administered 30 or 60 minutes later, the antibiotic efficacy proved to be lower by 90 or 76.6 per cent, respectively. The intoxication in later periods (in 90-120 minutes) resulted in a decrease in animal survival up to 40-15 per cent. It was demonstrated on the model of the plague infection in albino mice that the use of amikacin, cefotaxime, rifampicin or doxycycline during polymyxin therapy at the stage of marked generalization of the infection provided a significant increase in the animal survival (60 to 80 per cent) as compared to that after the use of the same drugs alone (0 to 20 per cent).
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PMID:[Detoxifying effect of antibiotics and their effectiveness in experimental plague at the stage of explicit intoxication]. 130 Sep 33

The effectiveness of some vaccine preparations for the revaccination of hamadryas baboons after their primary immunization with live plague vaccine " NIIS " administered in the form of aerosol was studied. The study was carried out under the conditions of the aerosol challenge of the animals with Y. pestis. The subcutaneous injection of plague vaccine " NIIS " was found to have advantages over its aerosol administration. Revaccination with Y. pestis fraction I, absorbed, was found to be 8 times more effective than the administration of plague vaccine " NIIS " by inhalation and not inferior to the subcutaneous injection of this vaccine. Y. pestis lipopolysaccharide, when injected simultaneously with fraction I, produced an immunosuppressive effect. The development of chemical plague vaccine on the basis of fraction I, intended for revaccination, was shown to have good prospects.
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PMID:[Effectiveness of revaccinating hamadryas baboons with NISS live dried plague vaccine and fraction I of the plague microbe]. 674 59

The dependence of the amount of electrokinetic potential in cells of Escherichia coli and Yersinia pestis, which differ in the rate of reduction of lipopolysaccharide (LPS), on the presence or absence of typical and atypical capsules of Y. pestis, encoded by intact and mutant fra operons, respectively, was studied. The ycaA+ycaF+(caf1 M+caf1+) genotype was shown to be expressed in serological stability of a classical capsular antigen, irrespective of the producer strain, and a decrease in the negative charge of microbial cells compared to their noncapsular variants. Blocking of the synthesis of the product of the ycaA gene of the fra operon resulted in formation of encapsulated bacteria, whose surface electricity and serological characters varied in dependence on the LPS structure. Data obtained support the assumption that a product of the ycA gene stabilizes the conformation of the typical capsule of the plague-causing agent, which was formed from YcaF (Caf1) monomers.
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PMID:[Electrokinetic potential of Yersinia pestis and Escherichia coli cells with an intact or defective ycaA gene (caf1M) of the fra-operon of plague pathogen]. 800 99

The efficiency of serological identification of Yersinia pestis strains which contain different plasmids was assessed with polyclonal and monoclonal immunoglobulin preparations in the direct fluorescent antibody method. Plague polyclonal luminescent immunoglobulins recognize only those Y. pestis strains which contain pPst, pFra plasmids or both. Anticapsular plague monoclonal antibodies interact only with capsule-forming plague agent strains (pFra+) grown at 37 degrees C. With plague monoclonal lipopolysaccharide antibodies one can identify all Y. pestis strains irrespective of their plasmid content and cultivation temperature. However, these antibodies cross-react with Yersinia pseudotuberculosis bacteria in 60% of cases. The problem of laboratory diagnosis of the plague organism, whatever its plasmid profile, can be solved through the development of a test kit involving two preparations such as plague lipopolysaccharide monoclonal luminescent antibodies and pseudotuberculosis specific luminescent adsorbed immunoglobulins.
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PMID:Identification of Yersinia pestis with varied plasmid composition using monoclonal and polyclonal fluorescent immunoglobulins. 847 14

Therapeutic efficacies of various drugs were studied comparatively in the treatment of experimental plague in albino mice at the stage of the infection generalization. It was shown that out of the tested drugs such as ciprofloxacin, amikacin, gentamicin, rifampicin and polymyxin B only ciprofloxacin provided a rather high therapeutic effect in the treatment of the plaque septic form. The in vitro and in vivo experiments demonstrated that ciprofloxacin had an antitoxic action on lipopolysaccharide (LPS) and the plague microbe toxin. In comparison to ciprofloxacin, polymyxin B had a higher neutralizing activity. It was found that the efficacy of the experimental plague treatment at the stage of the infection generalization increased with the use of combinations of the drugs with antitoxic and antibacterial activities (ciprofloxacin and polymyxin B).
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PMID:[Increased effectiveness of etiotropic therapy of experimental plague in albino mice at the stage of generalized infection]. 892 17

Species- and genus-specific antigenic determinants of total serological activity of plague agent lipopolysaccharide (LPS) were detected for the first time with a panel of monoclonal antibodies (MAb) in Y. pestis core polysaccharide in the R-form. MAb specifically bind radicals on one or several monosaccharides of core LPS. Galactose, fucose, and mannose contain common antigenic determinants for enterobacteria; glucosamine, glucose, ribose, xylose, and 2-ketodeoxyoctanoic acid (KDO) contain determinants for Y. pestis and Y. pseudotuberculosis; and epitopes differentiating the two latter agents by the carbohydrate component are localized on glucosamine, mannose, xylose, and KDO. Epitopes common for the Enterobacteriaceae family and species-specific epitopes, two of which are identic to core polysaccharide radicals, are situated on Y. pestis lipid A.
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PMID:[Study of antigenic determinants of Yersinia pestis lipopolysaccharide using monoclonal antibodies]. 981 23

There is limited information concerning the nature and extent of the immune response to the virulence determinants of Yersinia pestis during the course of plague infection. In this study, we evaluated the humoral immune response of mice that survived lethal Y. pestis aerosol challenge after antibiotic treatment. Such a model may replicate the clinical situation in humans and indicate which virulence determinants are expressed in vivo. Immunoglobulin G enzyme-linked immunosorbent assay and immunoblotting were performed by using purified, recombinant antigens including F1, V antigen, YpkA, YopH, YopM, YopB, YopD, YopN, YopE, YopK, plasminogen activator protease (Pla), and pH 6 antigen as well as purified lipopolysaccharide. The major antigens recognized by murine convalescent sera were F1, V antigen, YopH, YopM, YopD, and Pla. Early treatment with antibiotics tended to reduce the immune response and differences between antibiotic treatment regimens were noted. These results may indicate that only some virulence factors are expressed and/or immunogenic during infection. This information may prove useful for selecting potential vaccine candidates and for developing improved serologic diagnostic assays.
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PMID:Immune response to Yersinia outer proteins and other Yersinia pestis antigens after experimental plague infection in mice. 1008 37

Plague, one of the most devastating diseases of human history, is caused by Yersinia pestis. In this study, we analyzed the population genetic structure of Y. pestis and the two other pathogenic Yersinia species, Y. pseudotuberculosis and Y. enterocolitica. Fragments of five housekeeping genes and a gene involved in the synthesis of lipopolysaccharide were sequenced from 36 strains representing the global diversity of Y. pestis and from 12-13 strains from each of the other species. No sequence diversity was found in any Y. pestis gene, and these alleles were identical or nearly identical to alleles from Y. pseudotuberculosis. Thus, Y. pestis is a clone that evolved from Y. pseudotuberculosis 1,500-20,000 years ago, shortly before the first known pandemics of human plague. Three biovars (Antiqua, Medievalis, and Orientalis) have been distinguished by microbiologists within the Y. pestis clone. These biovars form distinct branches of a phylogenetic tree based on restriction fragment length polymorphisms of the locations of the IS100 insertion element. These data are consistent with previous inferences that Antiqua caused a plague pandemic in the sixth century, Medievalis caused the Black Death and subsequent epidemics during the second pandemic wave, and Orientalis caused the current plague pandemic.
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PMID:Yersinia pestis, the cause of plague, is a recently emerged clone of Yersinia pseudotuberculosis. 1057 Jan 95

Yersinia pestis, the causative agent of plague, and the enteropathogen Yersinia pseudotuberculosis have nearly identical nucleotide similarity yet cause markedly different diseases. To investigate this conundrum and to study Yersinia pathogenicity, we developed a high-density oligonucleotide array-based modification of signature-tagged mutagenesis (STM). Y. pseudotuberculosis YPIII mutants constructed with the tagged transposons were evaluated in the murine yersiniosis infection model. The DNA tags were amplified using biotinylated primers and hybridized to high-density oligonucleotide arrays containing DNA complementary to the tags. Comparison of the hybridization signals from input pools and output pools identified a mutant whose relative abundance was significantly reduced in the output pool. Sequence data from 31 transposon insertion regions was compared to the complete Y. pestis CO92 genome sequence. The 26 genes present in both species were found to be almost identical, but five Y. pseudotuberculosis genes identified through STM did not have counterparts in the Y. pestis genome and may contribute to the different tropisms in these closely related pathogens. Potential virulence genes identified include those involved in lipopolysaccharide biosynthesis, adhesion, phospholipase activity, iron assimilation, and gene regulation. The phospholipase A (PldA) mutant exhibited reduced phospholipase activity compared to the wild-type strain and in vivo attenuation of the mutant was confirmed. The combination of optimized double tag sequences and high-density array hybridization technology offers improved performance, efficiency, and reliability over classical STM and permits quantitative analysis of data.
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PMID:Application of high-density array-based signature-tagged mutagenesis to discover novel Yersinia virulence-associated genes. 1170 63


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