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S Kh Degtiarev

Publications and source records attributed to S Kh Degtiarev.

At least 19 recordsLinked to original sources
PubMed2004

[Restriction analysis of N-acetyltransferase 2 gene in Caucasian population of West Siberia].

Restriction analysis of the NAT2 gene was carried out in inhabitants of Novosibirsk. Polymorphism of this gene for nine known point mutations was studied in a sample of Novosibirsk residents consisting of 109 healthy Caucasians. The frequencies of these mutations did not significantly differ from the frequencies reported for Caucasian populations of other countries. In 79 patients with lung cancer, a region of the NAT2 gene that includes 29.7% of the coding sequence was analyzed for the new mutations by the RFLP analysis. No new mutations were found in this group.

Arylamine N-Acetyltransferase↗
PubMed2000

[New rare cutting restriction endonuclease SmII from Streptococcus milleri recognises 5'-ATTTAAAT-3'].

New restriction endonuclease (restrictase) Smil of type II was detected in the bacterial strain Streptococcus milleri. Cellular lysate enzyme cut T7 and adenovirus-2 DNAs at site 5'-ATTT decreases AAAT-3' but not lambda DNA which does not contain this sequence. Intense aeration inhibited the growth of S. milleri. The content of restrictase in the cells was the greatest during the logarithmic growth phase. A total of 20,000 units of Smil were isolated from 4 g of cells by cellular extract fractionation with ammonium sulfate and subsequent chromatography on columns with Bio Gel A 0.5 m, heparin agarose, and phosphocellulose. Purified enzyme cut the synthetic oligonucleotide duplex in the center of the recognized site 5'-ATTT decreases AAAT-3'. Smil restrictase is a true isoschisomer of rare-cutting Swal enzyme. Smil belongs to a small group of enzymes which recognize octanucleotide sites and can be used for large-block fragmentation of DNA. Comparison of specificities of rare-cutting and other restrictases suggests that the enzymes recognizing octanucleotides can evolutionally originate from enzymes recognizing both hexanucleotides and tetranucleotides.

Adenoviridae↗
PubMed2000

[A rapid method for testing the activity of the repair enzyme uracil-DNA-glycosylase].

A rapid and effective method of testing of a repair enzyme, uracil-DNA-glycosylase, was proposed. As a substrate, a deoxyuridine-containing 5'-32P-labeled deoxyoligonucleotide covalently attached to a polystyrene support (Tenta Gel S-NH2) was used. The ammonia cleavage of the apyrimidine site formed in the enzymic reaction followed by the transition of the labeled oligonucleotide fragment from the solid phase into solution allowed the detection of the enzymic activity.

Base Sequence↗
PubMed1999

[New reagents for affinity modification of biopolymers. Photoaffinity modification of Tte-DNA polymerase].

Arylazides N-(4-azido-2,5-difluoro-3-chloropyridinyl-6)-beta-alanine (Ia) and N-(4-azido-2,5-difluoro-3-chloropyridinyl-6)-glycine (Ib) were synthesized and covalently attached to 5-(3-aminopropenyl-1)-dUTP through the amino group to give 5'-triphosphate (IIa) and 5'-triphosphate (IIb). The resulting azides were subjected to photolysis in aqueous solution. The spectral and photochemical characteristics of azides (I) and (II) imply that their use for the modification of biopolymers holds promise. Compounds (IIa, b) effectively substituted dTTP in DNA polymerization catalyzed by thermostable DNA polymerase from Thermus thermophilus B-35 (Tte DNA polymerase). Photoaffinity modification of Tte DNA polymerase was carried out by dTTP analogues (IIa, b) and by earlier obtained 5-[N-(5-azido-2-nitrobenzoyl)-trans-3-aminopropenyl-1]deoxyuridine 5'-triphosphate (III) and 5-[N-(4-azido-2,3,5,6-tetrafluorobenzyol)-trans-3- aminopropenyl-1]deoxyuridine 5'-triphosphate (IV) using two variants of labeling. All four dTTP analogues were shown to modify Tte DNA polymerase.

Azides↗
PubMed1998

[Restriction endonuclease Sse9I (correction of Sse91) from Sporosarcina strain SP.9D recognizes the 5'-AATT-3' DNA sequence].

Sse91, a type II restriction endonuclease, has been isolated from Sporosarcina species 9D. The recognition sequence and cleavage point of restriction endonuclease Sse91 have been determined as 5'-decrease AATT-3'. The new enzyme is an isoschizomer of Tsp5091, but its optimal incubation temperature is 55 degrees C and it is inactivated at 65 degrees C for 20 min.

DNA↗
PubMed1990

[Detection of aquatic microorganisms from the Black Sea--producers of restriction endonucleases].

300 clones of microorganisms isolated at different stations and from different depths in the Black Sea were screened for restriction endonucleases production. The production of restriction endonucleases was found in 17 clones screened. Three of them were identified to be Alteromonas haloplanktis B1. Restriction endonuclease AhaB1 is an isoshizomer of Sau961. An identified Alteromonas haloplanktis clone B8 produces AhaB8I restriction endonuclease the prototype to which is KpnI. Of the clones isolated three are Moraxella species B4 producing MapB4I restriction endonuclease analogous to BanI, three are Bacillus species producing BspB2I and one is Micrococcus lylae 113 producing Mly1131 analogue of NarI, six Moraxella species B6 produce MspB6I. The isolated producer strains may be used for isolation of above mentioned restriction endonucleases.

Bacteria↗
PubMed1989

[Plasmids pMB123 and pMB124--vectors for obtaining subfragments of DNA with random "sticky" ends].

For preparing a DNA fragment with unique protruding ends, plasmid vectors pMB123 and pMB124 were constructed by inserting a synthetic polylinker into plasmid pUR222 at the EcoRI-PstI sites. The polylinker contains two FokI and HgaI sites at its ends in opposite orientation flanking a combination of SalGI, AccI, HindII, HindIII (the latter site is absent from pMB124) and BamHI sites. DNA fragment cloned at the SalGI and BamHI sites can be regenerated by either FokI or HgaI treatment, the SalGI and BamHI sites being deleted from the cloned sequence. Fragments coding for parts of human interleukin-2 were cloned in these vectors.

Autoradiography↗
PubMed1989

[Covalent labelling of the Klenow fragment of DNA-polymerase I from E. coli].

Incubation of the Klenow fragment of E. coli DNA polymerase I with [alpha-32P] dNTP (or NTP) results in the covalent radiolabelling of the enzyme, the bond being stable in acid (pH 2) and alkaline (pH 12) conditions and nucleophiles, such as beta-mercaptoethylamine, efficiently inhibiting the labelling. It is suggested that radiolabelling of the enzyme is the result of formation of chemically active products of the radiolysis of [alpha-32P]NTP (which are likely to be radicals). Non-radioactive NTP hinder the labelling, whereas Mg2+ and polynucleotide do not affect it. Cleavage of the enzyme by hydroxylamine and cyanogen bromide and analysis of gel-electrophoretic patterns of the cleavage products led to conclusion that 32P-label is located between Gly-544 and Met-647.

Chromatography, High Pressure Liquid↗
PubMed1987

[Substrate specificity of restriction endonuclease VspI].

The recognition sequence and cleavage point of restriction endonuclease VspI have been determined as 5'-AT decreases TAAT. This enzyme is not isoschizomer of any known restriction endonucleases. DNA pBR322 contains a single VspI recognition sequence in position 3539. Therefore this enzyme may be used for cloning DNA in the VspI site in AmpR-gene of pBR322.

Base Sequence↗
PubMed1987

[Specificity of restriction endonuclease VneI].

The recognition sequence and cleavage point of restriction endonuclease VneI have been determined as 5'-G decreases TGCAC. This enzyme is not isoschizomer of any known restriction endonucleases and therefore may be widely used in investigation of DNA structure.

Base Sequence↗
PubMed1986

[Cleavage of DNA adsorbed on the surface of phospholipid membranes by restrictases type II].

Cleavage of phage lambda DNA by restriction endonucleases in the presence of model phosphatidylcholine membranes was studied. Bsp1, Pst1 and Bam H1 were found to cleave DNA under these conditions to a considerably decreased extent. This effect does not result from irreversible inactivation of the enzymes or their direct interaction with the membranes. The most probable explanation of the membrane inhibitory effect is the change of DNA substrate properties resulting from its Mg2+-mediated binding to the membranes.

Adsorption↗
PubMedDate not supplied

[Photoreactive dTTP analogues as substrates for thermostable DNA polymerase from Thermus thermophilus B35].

Substrate properties of several dTTP analogues bearing a photoreactive 2-nitro-5-azidobenzoyl (NAB) group attached at position 5 of uracil through linkers of various lengths, dTTP-NAB-x-dUTP (where x = 2, 4, 7-13 is the number of atoms in the linker), were studied. All the analogues are substrates for thermostable Thermus thermophilus B35 DNA polymerase in the elongation reaction of the 5'-32P-labeled primer-template complex. The kinetic parameters of some of the analogues were determined and compared with those of natural dTTP. It was shown that an increase in the linker length results in a higher efficiency of the analogue. The incorporation of NAB-x-dUMP residues into the 3'-primer end did not impede a further elongation of the chain in the presence of natural dNTP.

Azides↗