[Polymorphism of tox and dtxR genes in circulating strains of Corynebacterium diphtheriae].

Polymorphism of tox and dtxR genes responsible for diphtheria toxin synthesis was revealed. Seven point mutations in tox gene were detected; study of their combinations allowed to determine 10 allelic variants of the tox gene in C. diphtheriae strains.

[Molecular typing of the strains of Bordetella pertussis circulating in St. Petersburg during an outbreak of the disease].

Growth of the whooping-cough morbidity during the last years in Russia and other countries with 40-year-long history of immunization gave rise to significant interest of researchers to variability of the Bordetella pertussis population. Comparative assay of the genomes of the B. pertussis strains circulating in St.

[The adhesive properties of meningococci from serogroups A, B and C].

The adhesive properties of 261 meningococcal strains have been studied by the methods of the hemagglutination test, the test of adhesion on buccal epithelial cells and electron microscopy. The study has revealed that adhesive properties can be observed in the strains of all groups under study (A, B and C) isolated from patients and carriers, including those isolated from the nasopharynx, blood and liquor, adhesive properties occurring in newly isolated strains with greater frequency than in museum ones. The simultaneous use of all three above-mentioned methods increases the possibility of the detection of meningococcal strains with adhesive activity.

Coenzyme non-specific glutamate dehydrogenase from Chlorella pyrenoidosa 82T: electron microscopic studies.

The constitutive coenzyme non-specific glutamate dehydrogenase (GDH) from Chlorella pyrenoidosa 82T was purified to homogeneity by column immunoaffinity chromatography and examined by an electron microscope. The enzyme molecule was found to be a hexameric oligomer composed of monomers arranged in three 2-point group symmetry in two layers slightly twisted round the 3-fold axis. The molecule is 8 +/- 1 nm in diameter and 10 +/- 1 nm in height.