[Properties of the Burkholderia pseudomallei insertional mutants deficient in membrane proteins production].

Transposon-induced B. pseudomallei mutants deficient in membrane proteins production were obtained for evaluation of the functional role of these cell components. In comparison with the wild type strain B. pseudomallei 57576, mutant clones TTM6, TTM7 and TTM9 carrying Tn5 chromosome insertions were characterized by lost or decreased production of outer membrane proteins 27, 48, 52, 150, 200 kDa. Alterations in outer membrane protein spectra were accompanied by twofold increase in susceptibility of bacteria to fluoroquinolones (pefloxacin, ofloxacin) and cephalosporins (ceftazidime) and noticeable reduction of virulence for white mice and guinea pigs in contrast to the initial strain, the obtained mutants were also less resistant in in vitro phagocyte killing.

[Cross-reacting antigens of pathogenic Burkholderia and some dangerous causative agents of infectious diseases].

Cross-reacting antigens in B. mallei, B. pseudomallei, B. thailandensis, Francisella tularensis, Yersinia pestis and Mycobacterium tuberculosis were studied with the use of immuno- and electrophoretic techniques. The set of antigens was shown to be almost identical in the causative agents of glanders, melioidosis, as well as in B. thailandensis, though in the latter organism 200-kD glycoprotein was absent. The analysis of immuno- and proteinograms demonstrated the presence of cross-reactions in the representatives of the genus Burkholderia with the causative agents of plague, tularemia and tuberculosis, which served as the basis for making the scheme of their antigenic relationships. The use of immunosorption techniques with subsequent analysis of the preparations by means of the SDS polyacryl gel electrophoresis and immunoblotting made it possible to characterize cross-reacting antigens of the pathogenic microorganisms under study, to establish their molecular weights (81-15 kD) and to show that some detected antigens are analogous to B. pseudomallei outer membrane proteins (34 and 30 kD).

[A species-specific DNA probe for identifying toxic strains of anthrax pathogens]. / Vidospetsificheskii DNK-zond dlia identifikatsii toksigennykh shtammov vozbuditelia sibirskoi iazvy.

On the plasmid DNA pOX01 of the anthrax pathogen two BamHI fragments were localized which facilitate detection of the Bacillus anthracis strains carrying pXO1 replicon. These fragments, after complete hydrolysis of plasmid DNA by HindIII, were cloned on the vector plasmids pUC19 and pBR322 by the "shot-gun" method in Escherichia coli cells. It is shown that the 900 bp BamHI/HindIII fragment from the pZAT1 recombinant plasmid has an ability for specific hybridization with DNA of toxigenic strains of B. anthracis and could be used as species-specific anthracic DNA probe which identifies toxigenic strains of the anthrax pathogen differentiating it from the other species of Bacillus genus as well as from the bacteria of other taxonomy groups.