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T A Smirnova

Publications and source records attributed to T A Smirnova.

At least 109 records · Page 6Linked to original sources
PubMedDate not supplied

[Bacteriocin-like factor in Bacillus thuringiensis].

The paper describes Bacillus thuringiensis var. galleriae strains possessing a bacteriocin-like factor (factor K) which inhibits the cultures of a number of serotypes of Bac. thuringiensis. The K+ cultures exhibit no antibacterial effect on other gram-positive and gram-negative microorganisms. The maximal level of factor K is found by the 8--9th hour of cultivation. No correlation has been established between the strucutred elements in the preparations of K+ cultures and the antibacterial activity. Apparently, factor K can be transferred to other strains.

Antibiosis↗
PubMedDate not supplied

[Electron microscopic study of the interaction between phages and Bacillus thuringiensis cells].

The interaction of phages belonging to different morphological groups with the cells of Bacillus thuringiensis var. galleriae R and S variants was studied. No adsorption of phages Tg11 and Tg18 on the cells of R variant was found upon infection in a liquid medium. What is characteristic of phage Tg11 is that it is predominantly adsorbed at the poles of S variant cells. Phage Tg18 particles are uniformly distributed along the perimeter of S variant cells. Phage Tg13 is adsorbed on the both variant cells. Phage aggregates with the elements of cell walls having a tetrahonal assembly of the subunits can be revealed in phage Tg13 lysates. The size of the subunits is 7 nm and the distance between their centers is 11 nm. A structured element, apparently the T-layer, is involved in the adsorption of phage Tg13 on the cells.

Adsorption↗
PubMedDate not supplied

[Electron microscopic study of the cells of variants of Bacillus thuringiensis var. galleriae forming colonies with altered morphology].

Colonial-morphological variants of Bacillus thuringiensis var. Galleriae were studied by electron microscopy. The S variant was found to be asporogenous, whereas the R variant produced mature spores. Morphological modifications in the cell were followed in the course of sporulation. Spores were shown to have thin filamentous and tubular protrusions which had not been so far described in crystalliferous bacteria. Preparations from colonies of the R variant contained peculiar structures which resembled phage tails. A possible function of these structures is discussed.

Bacillus thuringiensis↗
PubMedDate not supplied

[Ultrastructure of the bacterial spores and crystals of various Bacillus thuringiensis serotypes].

Spores and crystals of various Bacillus thuringiensis serotypes were studied by electron microscopy. The serotypes were shown to differ in the fine structure of the exosporium and crystals. The packing parameters of morphological subunits were determined by analysing electron photomicrographs by the technique of optical diffraction and filtration. Some of the strains are characterised by hypersynthesis of surface spore structures. The individual morphological properties of crystals can be used for their differentiation.

Bacillus thuringiensis↗
PubMedDate not supplied

[Antibiotic sensitivity of Bacillus thuringiensis var. galleriae strains].

Bacillus thuringiensis strains forming colonies of the S and R morphology were found to be susceptible to streptomycin, chloramphenicol, rifampicin, neomycin, lincomycin, monomycin, kanamycin, and resistant to ampicillin and polymyxin. The S strains were shown to be susceptible to tetracycline (Tets), whereas the R strains were either susceptible (Tets) or resistant (Tetr). The population of Tetr strains was heterogeneous in its resistance to tetracycline (the frequency of Tetr cells was from 10(-4) to 1). The incubation with a subinhibiting concentration of tetracycline (2 micrograms/ml) caused "induction", which decreased in the presence of chloramphenicol, in the Tetr strains. No "induction" was detected in Tets strains. No significant differences were found in the plasmid composition of the Tets and Tetr strains, and no correlation was established between the presence of plasmids and the resistance to tetracycline. It may be concluded therefore that determinants for the resistance to tetracycline are located in the chromosomes. Possible factors causing the resistance to tetracycline in B. thuringiensis are discussed.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Effect of chronic exposure to carbon monoxide on the biochemical composition of human blood].

Protein, lipid and carbohydrate metabolism of men was investigated during their prolonged exposure to a closed atmosphere containing carbon monoxide at a concentration of 20-10 mg/m3. A 30-day exposure of test subjects to carbon monoxide at a concentration of 20-15 mg/m3 caused an increase of albumin, beta-globulins, total lipids, cholesterol, beta-lipoproteins in the serum and a decrease of the sugar concentration in the blood. A 90-day exposure of test subjects to carbon monoxide at a concentration of 10 mg/m3 did not bring about significant changes in the above parameters. The provocative test for glucose tolerance showed no changes in the glycaemic regulation.

Adult↗