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2.
Autoimmunity ; 7(4): 267-77, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1715196

RESUMO

The phenotype HLA-B27 is common in patients who develop reactive arthritis after having an infection. One hypothesis concerning the pathogenesis of reactive arthritis is that molecular mimicry between HLA-B27 and certain bacterial components might be involved. It is known that an infection with Yersinia is commonly associated with reactive arthritis in B27 positive patients. Therefore, we were interested to investigate whether cross-reactivity between Yersinia and HLA-B27 exists. A gene library of Yersinia pseudotuberculosis was created in the plasmid vector pUC13. One of the resulting clones contained a gene encoding an intracytoplasmic protein that seems to have partial epitope identity with HLA-B27. It reacted in western blot. ELISA and immunoprecipitation with three different HLA-B27 specific monoclonal and polyclonal antibodies of the IgG and IgM class. However DNA-sequencing of the cloned Yersinia gene and the predicted amino acid sequence revealed only a very remote similarity with HLA-B27 in the primary structure. Instead, an extremely high degree of similarity with the ribosomal protein L4 of the S10 operon of Escherichia coli was identified indicating that the protein encoded by the cloned Y. pseudotuberculosis gene is a corresponding ribosomal protein.


Assuntos
Artrite/imunologia , Proteínas de Bactérias/análise , Epitopos/análise , Antígeno HLA-B27/análise , Yersinia pseudotuberculosis/análise , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Sequência de Bases , Clonagem Molecular , Escherichia coli/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas Ribossômicas/genética , Homologia de Sequência do Ácido Nucleico , Yersinia pseudotuberculosis/genética
3.
Bioorg Khim ; 15(6): 763-72, 1989 Jun.
Artigo em Russo | MEDLINE | ID: mdl-2675850

RESUMO

Using spectroscopic methods (circular dichroism and intrinsic protein fluorescence) and immunoenzyme assay, changes in the spatial and antigenic structure of yersinin, porin from outer membrane of Yersinia pseudotuberculosis, were studied in solutions of ionic and non-ionic detergents at various temperatures and low pH values. Yersinin was shown to retain its secondary structure under various denaturation conditions, the content of regular structural patterns depending on specific action of the denaturation agent. Process of yersinin denaturation similarly to other membrane proteins appears to occur via two structural transitions: dissociation of oligomers and denaturation of monomers. At the first stage changes of quaternary structure accompanied by the loss of so called conformational determinants were observed. Temperature-dependent changes of monomers' tertiary structure affect antigenic activity of yersinin in a smaller degree.


Assuntos
Yersinia pseudotuberculosis/análise , Proteínas da Membrana Bacteriana Externa/análise , Dicroísmo Circular , Detergentes , Fluorescência , Concentração de Íons de Hidrogênio , Técnicas Imunoenzimáticas , Substâncias Macromoleculares , Conformação Proteica , Desnaturação Proteica , Relação Estrutura-Atividade
4.
Bioorg Khim ; 15(1): 104-10, 1989 Jan.
Artigo em Russo | MEDLINE | ID: mdl-2472792

RESUMO

An O-specific polysaccharide of Yersinia pseudotuberculosis serovar VII has been isolated and characterized. The polysaccharide consists of colitose, D-glucose and 2-acetamido-2-deoxy-D-galactose in the ratio 1 : 2 : 2. From the results of methylation analysis, partial acid hydrolysis, 1H and 13C NMR spectroscopy the structure of the repeating unit of the O-specific polysaccharide is deduced as follows:


Assuntos
Antígenos de Bactérias/análise , Lipopolissacarídeos/análise , Yersinia pseudotuberculosis/análise , Glucose/análise , Hidrólise , Espectroscopia de Ressonância Magnética , Metilação , Antígenos O , Yersinia pseudotuberculosis/imunologia
5.
Pediatr Infect Dis J ; 7(10): 686-9, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3054777

RESUMO

For evaluation of the efficacy of early treatment with ampicillin on the clinical course of Yersinia pseudotuberculosis infection in children, 136 patients were randomly assigned to receive either ampicillin or placebo. Subjects were those who were diagnosed as having Kawasaki syndrome and those who satisfied three of the following four criteria: fever; rash; abdominal symptoms; and a history of ingestion of untreated drinking water. Fifty-six patients had evidence of Y. pseudotuberculosis infection bacteriologically and/or serologically. Twenty-six were assigned to placebo and 28 to ampicillin. Ampicillin therapy did not show a significant benefit in shortening the duration of fever, diarrhea and abdominal pain or in preventing rash, erythema nodosum and acute renal failure. After 5 days of treatment none of the patients in the ampicillin group excreted the organism in the stool whereas 19 (90%) of 21 in the placebo group did (P less than 0.001). Ampicillin did not show a clinical benefit but reduced the fecal excretion of the organism.


Assuntos
Ampicilina/uso terapêutico , Yersiniose/tratamento farmacológico , Infecções por Yersinia pseudotuberculosis/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Feminino , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Distribuição Aleatória , Yersinia pseudotuberculosis/análise
6.
Biofizika ; 33(2): 288-92, 1988.
Artigo em Russo | MEDLINE | ID: mdl-3390479

RESUMO

Physical and chemical properties of LPPS in aqueous solutions were studied. Hydrodynamic characteristics of LPPS depend upon the input concentration and method of solution preparation. Equation parameters for the relationship between [eta] and M omega were determined, and it was found that LPPS behavior in solution can be determined by the equation: [eta] = 5.5.10(-4).M0.57. In aqueous solutions complex macromolecules form compact particles ranging from 8 to 14 nm in size.


Assuntos
Proteínas de Bactérias/análise , Lipopolissacarídeos/análise , Yersinia pseudotuberculosis/análise , Cromatografia em Gel , Métodos , Peso Molecular , Soluções , Viscosidade , Yersinia pseudotuberculosis/imunologia
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