[Variability of Bacillus thuringiensis bacteriophages with C2-morphology].

Biological as well as physicochemical properties of Bacillus thuringiensis bacteriophages "17" and "7/13" having C2-morphology and isolated from factory phagolysates were studied. The bacteriophages are identical in the lytic spectrum++, morphology, size, GC-content, have the same buoyant density. The physical map for restriction endonucleases EcoRI, HindIII, SalGI and MvaI has been constructed of the bacteriophages DNA.

[Electrophoretic mobility of UV-irradiated bacterial cells].

Electrophoretic mobility of Escherichia coli cells exposed to various doses of UV-radiation was investigated. The method of free flow electrophoresis was used to study a correlation between membrane protein charge and cell surface electric charge. The change in the cell surface charge and electrophoretic motility was associated with the damage to membrane proteins and the survival of UV-irradiated bacteria.

[Changes in the electrical characteristics of bacterial cells in the disruption of the barrier function of the cytoplasmic membrane].

A change in the electro-orientation spectrum followed by a change in the electric characteristics of bacterial cells had been measured when the barrier function of the cytoplasmic membrane was disordered under the action of damaging physical and chemical factors. Analysis of changes in the spectra at a frequency of 10(4) to 10(7) Hz allows one to estimate the degree of cell damage in quantitative terms. The paper presents the results of comparing three procedures for such an estimation: inoculation onto solid growth media; linear regression analysis of an electro-orientation spectrum; comparison of the electro-orientation effect at a high frequency (ca.

[Chemical mutagenesis and the use of indirect enzymatic criteria for the selection of virulent clones of Bacillus thuringiensis].

The effect of the mutagene nitrosoguanidine (N-methyl-N'-nitro-N-nitrosoguanidine) on the growth of Bacillus thuringiensis subsp. galleriae st. 69/6 was being studied.

[BbvII--a new site-specific endonuclease from Bacillus brevis 80].

BbvII, a new site-specific endonuclease, has been isolated from Bacillus brevis 80 by gel-filtration and chromatography on heparin-Sepharose. The endonuclease recognizes a non-symmetrical sequence 5'-GTCTTC-3' in double-stranded DNA and cleaves DNA 3'-CAGAAG-5' in both strands outside the recognition sequence.

[Effect of dispersion of electric parameters of bacterial cells on their orientation in alternating electric fields].

On the basis of electrophysical model of bacterial cell frequency relationship of orienting force moment acting on it in the alternating electric field has been calculated. Dependence of relative value of the moment on electric and geometrical parameters of the model was calculated. It has been shown that the account of frequency dispersion of the electric parameters brings about a change in the course of frequency relationship of the orienting moment in the range of low and mean frequencies.

[Stereochemical theory of the 3-dimensional structure of globular proteins. I. Highly helical intermediate structures].

The authors analyze the physical prerequisites on which the proposed stereochemical theory of the three-dimensional structure of globular proteins is based. The theory represents a stereochemical modelling of the mechanism of protein self-organization suggested earlier by one of the authors. According to this mechanism, a highly helical intermediate structure(s) is formed at first and then it passes into the native one.

[Stereochemical theory of the 3-dimensional structure of globular proteins. III. Prediction of the tertiary structure].

A prediction is made of the tertiary structure of parvalbumin, the variable part of the immunoglobulin molecule, carboxypeptidase and the trypsin inhibitor. The structures obtained theoretically coincide completely with the native ones. In the case of the trypsin inhibitor molecule, the theoretical sequence of disulfide bridge formation completely coincides with the experimental data.

Simulation of the dynamics of nitrogen metabolism in sheep.

1. The results of isotope tracer studies of the dynamics of nitrogen metabolism in mature sheep were used to construct a seven-pool mathematical model. 2.

[Calculation of DNA molecule packing in crystals by the method of atom-atom potentials I. B-form of DNA].

The van-der-Waals interaction of DNA molecules in the B-form has been studied by the method of atom-atom potentials. This study was carried out to clarify to what degree does this interaction determinate packing of DNA molecules in a crystal lattice. Interaction energy of two parallel molecules has been calculated as a function of 4 parameters (interaxial distance, axial shift, screw rotation of molecules).