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T M Grigor'eva

Publications and source records attributed to T M Grigor'eva.

12 recordsLinked to original sources
PubMed1990

[Conjugation transfer of the pAMbeta1 plasmid to Bacillus anthracis].

The possibility of conjugational transfer of the plasmid pAM beta 1 in the cells of different strains of Bacillus anthracis has been established. The efficiency of the plasmid replicon transfer in interspecies transfer B. thuringiensis X B. anthracis was n.10(-7), while in interspecies transfer it was n.10(-6). The capability of mobilization of extrachromosomal replicon pTG141 for conjugational transfer has been demonstrated. Bacillus anthracis transconjugants harbouring the pAM beta 1 plasmid have acquired the donor properties in conjugation.

Bacillus anthracis↗
PubMed1989

[Plasmid transduction by Bacillus anthracis bacteriophage CP54].

Possibility of plasmid transduction in Bacillus anthracis vaccine strains Sterne and STI-1 by bacteriophage CP54ant having an increased ability of adsorbtion and a shortened period of latent development in Bacillus anthracis cells has been isolated. The main parameters of plasmid transduction by the bacteriophage have been established for the plasmid pTG141 (TcR). They include the effect of multiplicity of infection, the level of UV-inactivation of bacteriophage, the presence of antiphage serum in the incubation medium. Plasmid transduction by the mutant phage CP54ant was found to be more efficient as compared with the one by the parent phage. The isolated transductants served as donors of the transduced plasmid for Bacillus anthracis and Bacillus thuringiensis strains.

Bacillus anthracis↗
PubMed1987

[Homologous and heterologous transcription of the Cry+-plasmid in Bacillus thuringiensis].

The possibility of homologous and heterologous transception of Cry+ plasmids in Bacillus thuringiensis is demonstrated. Cry+ plasmids from crystal bearing strain of Bacillus thuringiensis were transferred into acrystalline strain belonging to H5 serotype by mutual incubation. The donor strain was previously marked by the transmissive plasmid pAM beta 1 coding for erythromycin and lincomycin resistance. The transcipients having acquired the ability to synthesize delta-endotoxin were referred to H5 serotype due to their phenotype. By analogous method Cry+ plasmid was transferred from Bacillus thuringiensis to Bacillus cereus. Bacillus cereus strain GP7 was used as a recipient strain resistant to tetracycline. The presence of delta-endotoxin in transcipients was confirmed by bioprobes and immunoenzyme assay. To prove the transfer of Cry+ plasmid the plasmid profiles of the parent strains and transcipients have been analyzed. The formation of cellular contacts during mutual incubation of Bacillus thuringiensis and Bacillus cereus strains was demonstrated by electron microscopic study of ultrafine cuts.

Bacillus thuringiensis↗
PubMed1983

[Simultaneous reversion for genes thy, dra and drm in Bacillus thuringiensis].

The reversions of mutations in genes thy, dra (deoxyriboaldolase) and drm (phosphodeoxyribomutase) were studied in Bacillus thuringiensis var. galleriae 351. In this strain, both dra and drm mutants are sensitive to the presence of thymidine (Tds). In addition to the reversions for one of the properties (thymine requirement or sensitivity to thymidine), the simultaneous reversions for both properties (Thy + Tdr) were indicated. The frequency of Thy + Tdr revertants varied from 10(-4) to 10(-8), depending on both a selection method and the conditions of preliminary cultivation. The Thy + Tdr revertants had a rough (R) colony morphology in 100% of the cases, though the parental strains were of smooth (S) colony morphology. Selection for R variants, visually or by means of screening for Tg4 resistant or tetracycline resistant clones, resulted in detecting double Thy + Tdr revertants in 100% of the cases. The parental Thy - Tds phenotype restored after R leads to S conversion which occurred at the frequency 10(-7) to 10(-8) and might be detected by means of streptomycine selection.

Aldehyde-Lyases↗
PubMed1980

[Detection of atypically light and immunologically defective erythrocytes in paroxysmal nocturnal hemoglobinuria].

Atypically light red cells were detected at the plasma--phycoll solution (with a specific gravity of 1.077) boundary in 24 out of 26 patients with paroxysmal nocturmal hemoglobinuria (PNH) by means of centrifugation of the patients' blood in 600 g density gradient for 30 minutes. Atypically light red cells have a decreased amount of Rh-antigen and the positive Coombs direct test after addition of anticomplement serum. As a result of splenectomy patients with autoimmune hemolytic and hypoplastic anemia showed the appearance of atypically light cells in the upper layer the first day after the operation. It is suggested that the presence of atypically light red cells is connected with the deficient immune system in patients with PNH, specifically with insufficiency of the spleen function to eliminate the defective red cells.

ABO Blood-Group System↗