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T I Tikhonenko

Publications and source records attributed to T I Tikhonenko.

173 records · Page 10Linked to original sources
PubMedDate not supplied

[Mapping of lengthy changes in the genomes of lambda-phages by using restriction endonucleases].

Fragmentation and mapping of DNA of two derivatives of lambda-phage, lambdapgal and lambda delta were done using restricting endonucleases R. EcoRI, R. BamHI, and R. SmaI. In DNA of lambdapgal phage a fragment of chromosome lambda of the wild type with molecular mass of 3.7--4.7 megadaltons to the left of the integration site was replaced with a fragment of chromosome of E. coli with the molecular mass of 2.3--3.3 MD containing a complete galactose operon. In the chromosome of lambda delta phage as compared with lambda-phage of the wild type there is a deletion of 5.2 MD in size. The localization of the deletion was determined. Possible ways of using DNA of lambdapgal in genetic engineering studies as the "pure" source of gal-operon for its transplantation using various restricting endonucleases are discussed.

Coliphages↗
PubMedDate not supplied

[Comparative characteristics of PBV-1 and PBV-3 viruses isolated from Penicillium breve-compactum].

PBV-1 and PBV-3 viruses isolated from mycelium of Penicillium brevi-compactum show similar morphology and practically the same size of virus particles. Both viruses have been shown to lyse very effectively E. coli C, K12, W3350, CR63. Reproduction of the viruses in E. coli CK cells is limited due to the phenomenon of modification by the host, and negative colonies formed by each on E. coli CK sheet differ in morphology. PBV-1 virus is highly infectious for E. coli B, while the capacity of PBV-3 to multiply in these cells is very low. The limited reproduction appears to be explained by modification of PBV-3 DNA in the E. coli B system. PBV-1 and PBV-3 viruses have been shown to differ serologically, although serological cross reactions indicate their antigenic relationship. The two viruses under study differ in the constituency and molecular weight of the main structural proteins: 36,000: 28,000: 26,500 and 17,000 daltons for PBV-1 and 39,000; 36,000; 32,500; 31,000 and 18,000 daltons for PBV-2.

Antigens, Viral↗
PubMedDate not supplied

[Fragmentation of human adenovirus type 6 DNA by means of restrictase of E. co R I and BAM I].

The effect of restricting endonucleases of E. co RI and BAMI on DNA of human adenovirus type 6 was studied. E. co RI and BAMI restrictases cleave virus DNA into 4 fragments each. The molecular weight of E. co RI fragments was: A--17.5X10(6), B--3.63X10(6), C--1.56X10(6), D--1.05X10(6), those of BAMI fragments: A--9.7X10(6), B--7X10(6), C--4.09X10(6), D--3.1X10(6). By means of terminal nucleotidyltransferase and the procedure of partial DNA hydrolysis, the alteration of fragments obtained by the effect of E. co RI enzyme in adenovirus type 6 genome was determined and found to be A--D--C--B.

Adenoviruses, Human↗
PubMedDate not supplied

[Use of U3 promotor from the LTR region of bovine leukemia virus for expressing genes for antiviral antisense RNAs in cell cultures].

The possibility was studied to use the U3 promoter from LTR region of bovine leukemia virus to control the expression of the antisense RNA genes directed against the BLV genome in cell cultures FLK-BLV, CC81, and HeLa. The genetic engineering constructions were obtained carrying the reporter beta-galactosidase gene and the genome of antisense RNA to R-U5 region of the viral genome under the control of the promoter. The functioning of the viral promoter was studied in three cell lines. Its specific activation and kinetics of inhibition of BLV virus reproduction in cell culture CC81 have been demonstrated. The maximal 75% level of the viral reproduction inhibition was achieved at threefold molar excess of the plasmid containing the antisense RNA gene over the pregenomic viral DNA.

Antiviral Agents↗
PubMedDate not supplied

[Study of conditions for cleaving bovine leukemia virus RNA in vitro using ribozymes directed against long terminal repeats].

Ribozyme has been constructed by the oligonucleotide synthesis technique that is capable of splitting bovine leukemia virus (BLV) RNA-substrate in the R-region (358th nucleotide). Ribozyme has been shown to efficiently split the RNA containing R-region of the virus. The efficiency of ribozyme function depends on conditions of the reaction reaching its maximum at 25 degrees C and pH 7.3-7.6. The efficiency of splitting is increased by multiple heating-cooling cycles of the substrate-ribozyme mixture.

Base Sequence↗
PubMedDate not supplied

[Analysis of RAT2 cells, transformed by the CELO (FAV1) virus, using the polymerase chain reaction].

DNAs extracted from the RAT2 cells transformed by the CELO virus (strain Phelps) have been analyzed by polymerase chain reaction. Sequences belonging to the left end of the viral genome (according to Ishibashi & Yasue, 1984) were not found in the tested DNAs. On the other hand, the polymerase chain reaction data have revealed the presence of fragments specific of the opposite end. We conclude that this region may have included the genes responsible for cell transformation, at least as far as Phelps viral strain is concerned.

Animals↗
PubMedDate not supplied

[Suppression of replication of swine parvoviral antisense RNA against the NS PPV gene in swine thyroid gland cells].

The possibility of suppression of porcine parvovirus (PPV) reproduction in the culture of thyroid gland cells of a swine that contain the integrated genes for asRNA against the nonstructural proteins of the virus has been studied. 10 cell lines with the asRNA genes have been obtained. The line with the maximal number of integrated gene copies was used to inflict with the parvovirus. The expression of asRNA in this cell line was shown to lead to 95% suppression of PPV replication as compared with the control cell line.

Animals↗
PubMedDate not supplied

[Preparation of a non-defective adenovirus vector based on the Ad5 genome with the E3 region replaced with plasmid DNA with a kanamycin- resistance gene].

The plasmid pH5KV14 containing the right end of the Ad5 viral genome (45-100 map units) with deleted nonessential E3 region (78.5-84 map units) has been constructed. A helper-independent recombinant virus Ad5KV14 has been obtained as a result of in vivo transformation of the line 293 human cells by the pH5KV14 plasmid DNA and an EcoRI-A DNA fragment of the virus Ad5 and subsequent recombination. A nondefective recombinant virus Ad5KV17 containing the Ad5 genome with the E3 region substituted for the plasmid DNA fragment coding for the kanamycin-resistance has been constructed by a similar procedure.

Adenoviridae↗
PubMedDate not supplied

[Presence of genomes of phage PBV-1 in the mycelia of the fungus Penicillium brevi-compactum].

The rate of reassociation of 3H-DNA of phage PBV-1 was increased in the presence of 100-fold excess of unlabeled DNA of Penicillium brevi-compactum. On this basis it was calculated that DNA isolated from Penicillium brevi-compactum contained 27--38 phage genomes per haploid cell genome, DNA of PBV-3 virus does not influence the rate of reassociation of PBV-1 virus DNA indicating the lack of homology between DNAs of PBV-1 and PBV-3 phages.

Bacteriophages↗