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T I Tikhonenko

Publications and source records attributed to T I Tikhonenko.

At least 55 records · Page 3Linked to original sources
PubMed1978

Analysis of the genome of type 7 simian adenovirus using restrictases.

The effect of the restricting endonucleases R.EcoRI, R.BamI and R.SalI on the genome of type 7 simian adenovirus (SA-7) has been studied. Since the DNA has only one site of R.EcoRI recognition the enzyme cleaves SA-7 DNA into two fragments with the molecular weights 12.0 and 10.0 . 10(6). The restrictase R.BamI cleaves the SA-7 DNA at six sites producing 7 fragments with the molecular weights 6.6, 5.9, 3.8, 2.7, 1.3, 0.7 and 0.6 . 10(6). R.SalI cleavage yields 6 fragments with the molecular weights 8.1, 5.5, 4.3, 2.45, 1.2 and 0.6 . 10(6). The R.BamI and R.SalI fragments are arranged in the orders E-A-D-F-C-G-B and A-B-D-F-E-C, respectively. The only R.EcoRI recognition site is localized in the C fragment produced by R.BamI and in the B fragment produced by R.SalI.

Adenoviridae↗
PubMed1978

[Formaldehyde-induced tight binding of protein to RNA in particles of rod-like virus].

The formaldehyde-induced formation of tightly bound RNA-protein complexes of rod-like plant viruses was studied. The preparations of tobacco mosaic virus and closely related cucumber virus 4 were incubated with 1.5% formaldehyde for 20-50 hrs at 50 degrees C. Then the viral particles were disrupted, free protein was removed and viral RNA was centrifuged in the linear gradient of Cs2SO4. The RNAs from the formaldehyde-untreated viruses and RNA from the formaldehyde-treated tobacco masaic virus had the density of 1.65-1.66 g/cm3, while RNA from the formaldehyde-treated cucumber virus had the density of 1.57-1.42 g/cm3, depending on the incubation time. This is indicative of the protein binding to RNA. Treatment of the cucumber virus complex with pronase resulted in a liberation of free RNA with the density of 1.66 g/cm3; incubation for 2 min at 100 degrees C in a dissociating mixture (2% sodium dodecyl sulfate + 0.2% mercaptoethanol) did not cause the dissociation of the complex. Polyacrylamide gel electrophoresis showed that the most part of the protein molecules are bound within the complex not by covalent protein-protein cross-links.

Formaldehyde↗
PubMed1977

[Transformation of the substrate specificity of EcoRI restrictase under the influence of glycerin].

The restriction endonuclease EcoRI hydrolyzes DNA to a greater number of fragments in the presence of glycerol than under normal conditions. This enzyme begins to work by the so-called EcoRI-type of restriction when glycerol concentration reaches 50%. The EcoRI activity appeared in experiments only when the ionic strength of the solution was decreased and pH of the solution was increased. However, under such extreme conditions the enzyme was quickly inactivated and it was difficult to obtain reproducible results especially for hydrolysis of the high-molecular DNA. The suggested conditions for the EcoRI activity permit to obtain reproducible results, this being practically equivalent to discovery of the new restriction endonuclease.

Adenoviruses, Human↗
PubMed1977

[Sensitivity of B- and C-DNA forms to modifications by O-methylhydroxylamine].

Effects of high concentrations of lithium, cesium and ammonium chlorides on the reaction ability of free CMP and cytosine in free DNA of CD phage with respect to O-methylhydroxylamine (OMHA) are studied. CMP reaction in all the cases takes place mainly for 24 hours. Like classical B-form, native DNA, having C-form in high ionic strength solution (as estimated from circular dichroism data), is not modificated. Thus, the access of some cytosine residues in intraphage DNA to OMHA is due not to the decreased DNA hydratation in situ, but to the presence of differently ordered regions in DNA.

Ammonium Chloride↗
PubMed1977

[Identification of CD phage proteins participating in DNA-protein interaction by means of O-methylhydroxylamine].

An early described hypothetical scheme is confirmed on transformation of non-covalent polynucleotide-protein interactions into covalent under the treatment of CD phage with O-methylhydroxylamine. 4 proteins are revealed, which have been covalently bound to cytosine of DNA during modification process. Fractionation of these proteins in polyacrylamide gel in the presence of sodium dodecylsulphate has revealed that three of them migrate as head structural proteins, and the rest--as internal phage CD protein. Possible mechanisms of the effect of phage protein on the reaction of DNA cytosine residues with O-methylhydroxylamine are discussed.

Bacteriophages↗
PubMed1976

[Bacteriophage T2 DNA modification by O-methylhydroxylamine].

A comparative study of the reactivities of free 5-hydroxymethylcytosine (5-HMC) and 5-HMC found in the composition of native, denaturated and intraphage DNA of the T2 phage with that of O-methylhydroxylamine (OMHA) demonstrated that the DNA secondary structure in situ is partially disturbed. The interaction DNA-protein in the phage particle channels the reaction into a predominant formation of 4N-methoxy-6-methoxyamino-5,6-dihydro-5-hydroxymethyl cytosine, but not 4N-methoxy-5-hydroxymethyl cytosine, which is formed in vitro. In the course of the reaction the interaction DNA-protein is probably fixed by covalent binding.

5-Methylcytosine↗
PubMed1976

[Colicin El synthesis in a cell-free system of paired transcription--translation].

Proteins were synthesized in the cell-free coupled transcription-translation systen (S30) under the control of the DNA-templates of plasmid ColEl, phages T2 and Sd. The most active templates were phage T2 DNA and closed plasmid DNA. Plasmid DNA induced synthesis of 8 individual proteins, one of which was a biologically active antibiotic of protein nature--colicin. The titre of colicin synthesized in such a cell-free system reached 1024 U/ml, this being about 100 times greater than the titre of this antibiotic in the colicinogenic bacteria cultures.

Cell-Free System↗
PubMed1975

[Bacteria-infectious viruses in Penicillium chrysogenum strains with differing antibiotic activity].

A new virus capable of replication on E. coli C was isolated from Penicillium chrysogenum. Six strains of P. chrysogenum differing in the cultural-morphological and biochemical properties and the titer of virus PBV5 were studied. The data provided a supposition that there were definite connections between the titer of virus PBV5 in the mycelium and the fungus ability for the antibiotic production.

Bacteriolysis↗