[Immunogenicity and safety of a prototype chemical anthrax vaccine in laboratory animal models].

Aim: Evaluation of immune stimulating and toxic effects of a vaccine prototype protein components.

Materials And Methods: Linear mice, guinea pigs and rabbits were immunized subcutaneously once or twice by recombinant protective antigen (rPA), S-layer protein (EA1) or their complex. Innate immunity structure activation was registered by changes in Toll-like receptor (TLR) expression.

[Identification of the differences in the genes responsible for methionine biosynthesis in Bacillus anthracis strains and phylogeny-related species].

The comparative analysis of the gene sequences encoding the synthesis of enzymes responsible for the intermediary metabolism of methionine in Bacillus anthracis strains and in closely related bacterial species was carried out. Deletion of 42 nucleotides in the hom2 gene, which determines the homoserinedehydrogenase, is detected in all tested Bacillus anthracis strains. In the strains of other bacillar species hom2 gene mutation, which blocks up the tracts of methionine and threonine biosynthesis, was not identified.

[Immunogenicity of protective antigen extracted from asporogenic recombinant strain Bacillus anthracis].

Aim: To study the ability of recombinant protective antigen (PA) to stimulate adaptive immune response in laboratory animals.

Materials And Methods: Vaccine, recombinant, and reference strains of Bacillus anthracis were used in the study. Laboratory animals were immunized subcutaneously with two doses of antigenic preparation or one dose of B.

[Current views on pathogenicity and immunogenicity factors of Bacillus anthracis].

Bacillus anthracis is an etiological agent of extremely dangerous zooanthroponosis - anthrax. To date, significant volume of scientific data about structure, molecular nature, characteristics, genetic determination, regulation and action mechanisms of main pathogenicity factors of B. anthracis and its immunogenicity is accumulated.

[Genomic polymorphism of the main subspecies of the plague agent strains].

Genomic fingerprinting analysis of plague agent strains of the main subspecies isolated in natural foci of various types in the Russian Federation and neighboring countries suggests their genetic polymorphism, while they are similar in phenotypic properties. The strains of the main subspecies, Y. pesis subsp.

[Immunogenicity of the recombinant Bacillus strains with cloned gene of biosynthesis of protective antigen against Bacillus anthracis].

Microbe Russian Anti-Plague Research Institute, Saratov A hybrid plasmid pUB110PA-1 demonstrating stable functioning in the cells of Bacillus strains and containing the gene of biosynthesis of Bacillus anthracis protective antigen was constructed. The recombinant strains surpassing the anthrax vaccinal cultures in the secreted synthesis of the protective antigen were obtained and their immunological efficacy was assessed. A single inoculation of Guinea pigs with the dose of 5 x 107 spores of the recombinant strains imparted efficient protection against B.

[Role of the components of the S-layer in immunogenicity of Bacillus anthracis].

The immunogenicity of proteins Sap and EA1, contained in B. anthracis S-layer, was evaluated in experiments on laboratory animals. These proteins were found to produce protective effect and could be regarded as additional immunogenic factors.

[Analysis of genomic polymorphism of typical and atypical strains of the plague pathogen using polymerase chain reaction with universal primers].

An analysis of genome polymorphism of the Y. pestis strains by using the method of polymerase chain reaction (PCR) for the tandem repeats of bacteriophage M13 DNA revealed a species similarity of both typical and atypical (according to diagnostic signs) plague-microbe strains. Strain Y.

[The range of pathogen variation due to discussion of different hypotheses of plaque].

The paper reviews the hypotheses that explain the mechanism of plague enzooty in natural foci, which are based on a concept of a wide range of plague microbial variability. A comparative analysis of the parameters of variability in the experimentally obtained plague microbial strains and "atypical" natural isolates of the causative agent has led to the conclusion that the mechanism of adaptive variability is due to a phenotypic change in ontogenesis that reflects the philogenetic pathway of the adaptability of a plague microbe to constantly changing living conditions in the ecological niche assimilated by the causative agent.

[Functional phenotypic variability in a plague pathogen and plague enzootics].

In the bacterial population, phenotypic variability plays a part of structural and functional subsystem that occupies a special place in the relations of heterogenic populations by performing an important adaptive function in the common system of ecological connections of parasitocenosis. At the same time regularly varying microorganism phenotypes act as an independent system that are closely related with the conditions of the niches occupied by the causative agent. Each subsystem as part of parasitocenosis is provided by its intrinsic adaptive mechanisms, which in combination ensures the stability of biocenosis based on self-regulation of evolutionarily established ecosystems.

[Genotyping Yersinia pestis strains from various natural foci].

Seven genetic variants of Yersinia pestis were detected by finger-printing of 85 strains of this bacterium from natural foci by means of a BX probe. Variants of Y. pestis strains correlate with certain species of carriers.

[Comparative study of the structure of some genetic probes used for typing Yersinia pestis strains].

A nucleotide sequence common for genetic probes used for detection and investigation of Y. pestis strains MK, IS100, and HRSIII was identified on the basis of restriction, hybridization, and computer analysis. This region of chromosomal DNA is a part of low-molecular BX-probe (about 170 bp) we have developed.

[Molecular genetic analysis of DNA structure of pFra plasmids in plague pathogen of varying biovar].

Data on comparative molecular genetic analysis of pFra plasmids from plague bacillus belonging to either two biovars (antiqua and orientalis) are presented. It was established that during evolution these replicons were rearranged, which resulted in the differences between pFra plasmids of plague bacillus of antiqua biovar (Yersinia pestis 231 and Y. pestis 358/12) and that of orientalis biovar (Y.

[Molecular genetic methods for detecting and identifying the plague microbe].

The review analyzes the data on the new designed drugs and ways of identification and detection of the plague causative agent. It gives the results obtained from molecular genetic studies in designing the diagnostic test system based on DNA [correction of DNK] probes and in developing a way of detecting the plague causative agent by the polymerase chain reaction.

[The determination of the content of the cholera toxin gene in the composition of the DNA from Vibrio cholerae strains by means of the nested polymerase chain reaction].

The possibility of detecting cholera toxin genes in V.cholerae enterotoxigenic strains by the method of "nested" polymerase chain reaction with the use of primers on the DNA area of operon ctx of AB genes. The possibility of the detection of several V.

[Phenotypic expression of the Ca2+-dependence trait in recombinant cells of Yersinia pestis (Lehmann, Neumann)].

A conceptual model of the Yersinia pestis Ca(2+)-dependence mechanism is proposed. The model is based on data from analyses of peculiarities of recombinant cells of this plague-causing agent carrying the cloned first Bg/II fragment of the Ca(2+)-dependence plasmid (pCaD) and a combination of this fragment and other plasmid pCaD fragments. The data obtained also allowed a revision of the role of the lcr GVH locus of pCaD in this phenomenon.

[A DNA analysis of Vibrio cholerae strains by the polymerase chain reaction].

The method for the analysis of cholera toxin gene in V. cholerae strains was developed on the basis of polymerase chain reaction (PCR). This specific and highly sensitive method using primers affecting the site of the DNA of the operon of cholera toxin gene made it possible to identify one copy of V.

[Genetic research on plague pathogen in plague control].

The results of molecular-genetic studies performed by Russian specialists in plague research are discussed. On their basis, new concepts concerning the factors determining virulence of the plague bacterium were formulated, and certain aspects of Yersinia taxonomy were clarified.

[A gene expression study and the isolation and immunobiological properties of the iron-regulated membrane proteins of the plague microbe].

The study has examined how the plague bacillus expresses genes of two high-molecular weight (190 and 240 kD) iron-regulated membrane proteins (HMWP). The latter were purified and assayed for their immunobiological properties in vitro and in vivo. DNA-probing (at E.

[Improvement of a method for detecting of strains of the plague microbe using polymerase chain reaction].

Three pairs of oligonucleotide primers, complementary to nucleotide sequences of Yersinia pestis plasmids (pPst, 9.5 kb; pCad, 70 kb; pFra, 95 kb), were used in polymerase chain reaction for high-sensitive specific detection of plague pathogen. Primer pairs P1,P2,C1,C2, and F1,F2 were used to amplify fragments of pla gene (plasmid pPst), yop1 gene (plasmid pCad of plague microbe), and caf1 gene (plasmid pFra), respectively.

[Design of a chromosomal DNA probe species specific for Yersinia pestis].

A 14.8 kb DNA fragment from the chromosome of Yersinia pestis TWJ was cloned and the restriction map constructed. The fragment designated as T16 and its subfragments were tested in dot-hybridization with strains of Yersinia genus and other members of Enterobacteriaceae.

[Constructing a test system for the identification of plague microbe based on genetic probes].

DNA probes for detection of the plague agent Yersinia pestis were made on a basis of its three typical extrachromosomal replicons. The recombinant plasmid pBS2 including pBR327 vector and SalGI-BspRI fragment of the plasmid pFra was constructed. The above fragment is connected with synthesis of Y.

[Design of a species-specific DNA probe based on the pFra plasmid of the plague pathogen].

The recombinant plasmid pBS1 carrying a 2 kb SalGI fragment of Yersinia pestis pFra plasmid was constructed by insertion of the fragment into a vector plasmid pBR327. SalGI-BspRI 400 bp subfragment was recloned into a pBR322 vector plasmid. Open reading frame was found in the fragment by DNA sequencing technique.