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E A Kudriavtseva

Publications and source records attributed to E A Kudriavtseva.

5 recordsLinked to original sources

[Development of a system of plasmid transfer in the strains Streptomyces avermitilis ATCC 31272 and Saccharopolyspora erythraea ATCC 11635 by the method of intergeneric conjugation].

A new method of plasmid DNA transfer from the donor strain Escherichia coli S17-1 to the erythomycin-producing strain Saccharopolyspora erythraea and avermectin-producing strain Streptomyces avermitilis via intergeneric conjugation was proposed. The optimal parameters of the method were chosen for increasing the efficiency of crosses and ensuring easily reproducible results. The behavior of the multicopy plasmid pPM803 and the integration vector pTO1 along with a number of new plasmids specially created by us, was examined in these strains. A new plasmid vector (pSI60) capable of integrating into the chromosome of actinomycetes at the integration site of the temperate actinophage phi C31 was constructed. This vector possesses unique sites convenient for cloning and may be stably maintained in exconjugants of S. avermitilis and in the model strain Streptomyces lividans. The gene encoding resistance to spectinomycin and streptomycin was cloned into the vector pSI60 in this strain. For cloning in strain Sac. erythraea, vectors pSI261-280, which integrate into the chromosome via homology with the cloned DNA and can be stably maintained in exconjugants, were constructed.

Attachment Sites, Microbiological↗

[Molecular genetic study of the strain Streptomyces virginiae-- the producer of virginiamycin].

The level and the character of the Streptomyces virginiae virginiamycin-producing strain's resistance to self-produced antibiotic and a number of antibiotics from different groups were determined. S. virginiae was shown to display constitutive and inducible resistance to self-produced antibiotic. The phenomenon of cross-inducible resistance of the strain to virginiamycin and the antibiotics erythromycin, oleandomycin, and thiostrepton was demonstrated. The pTO1 and pVGTB24 plasmids were introduced into the strain by the method of intergeneric conjugation with Escherichia coli. Site-specific integration of the pTO1 vector into the S. virginiae chromosomal attB site without disturbance of growth, differentiation, and productivity of the strain was shown. The multicopy autonomously replicating plasmids pIJ699, pIJ702, pWOR109, and the integrative pZAT22 plasmid were introduced into the strain via electrotransformation of germinating spores. The efficiency of transformation was 1-5 x 10(3) transformants per 1 microgram DNA. The stable inheritance of the plasmids in S. virginiae without structural rearrangements was shown. These results allow the use of these plasmids to clone genes into S. virginiae.

Anti-Bacterial Agents↗

[Use of a plasmid with integrative function of phage phiC31 for transfer of cloned genes into Streptomyces strains].

Opportunities for application of integrative vectors carrying the attP site and the int gene of the temperate actinophage phi C31 for cloning genes in Streptomyces strains were demonstrated. The behavior of the integrative vectors pZAT22 and pTO1 in the model strain S. lividans TK64 and in the bialaphos-producing strain S. hygroscopicus, respectively, was characterized. Restriction maps of the S. lividans and S. hygroscopicus chromosomal regions containing attB sites were constructed. The bar gene of resistance to bialaphos was incorporated into the chromosome of the model strain S. lividans via the integrative pZAT22 vector, the level of expression of this gene within the chromosome of a heterologous host was determined. The possibility of amplification of the bar gene in the chromosome of the strain S. lividans was shown. The conjugative integrative vector pTO1, which carried the cloned bar gene, was introduced into the bialaphos-producing strain by intergeneric matings of Escherichia coli and S. hygroscopicus. The effect of an additional copy of the gene in the chromosome of S. hygroscopicus on strain resistance and productivity was studied.

Bacteriophages↗