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N V Anikeĭcheva

Publications and source records attributed to N V Anikeĭcheva.

14 recordsLinked to original sources
PubMed1994

[Isolation, purification, and characteristics of the new restriction enzymes BciBI and BciBII, produced by Bacillus circulans].

New site-specific endonucleases BciBI and BciBII have been detected in Bacillus circulans. The enzymes were purified by fractionation of cell-free extract with polyethylene imine and ammonium sulphate (40-80% of saturation) followed by chromatography on DEAE-sepharose, blue-sepharose and phosphocellulose. The endonucleases BciBI and BciBII were separated only at the final step of the purification--by chromatography on the phosphocellulose column. The yields of BciBI and BciBII were 600 and 10,000 U/g of cells. It was found that restriction endonucleases BciBI and BciBII are isoschizomers of ClaI and BstNI, respectively.

Bacillus↗
PubMed1994

[New site-specific endonucleases from strains of Bacillus].

In a search for new restriction endonucleases type II, among forty bacterial strains of the Bacillus genus two strains producing site-specific endonucleases have been found. Endonucleases BbvAIII and BspFI, isolated from B. brevis BLM B-677 and B. species F, are shown to be true isoschisomers of BspMII (Kpn2I) and Sau3AI, respectively.

Bacillus↗
PubMed1992

[Specific endonuclease BbvBI from Bacillus brevis].

A new restriction endonuclease BbvBI free from contaminating nonspecific nucleases and phosphatases was isolated from the Bacillus brevis cells. The enzyme was purified by fractionating the sonicated cell-free extract in a two-phase PEG/dextran system and subsequent chromatographies on DEAE-sepharose, blue sepharose and heparin sepharose. The endonuclease BbvBI displayed the maximal activity at 45 degrees C, pH between 8.0 and 8.5, MgCl2 concentration in the range of 5-10 mM and at the low ionic strength. It is shown that the enzyme cleaves the sequence G'GYPC'C, with the preferential cleavage of GGTACC and GGCACC sites as compared with GGTGCC and GGCGCC. Thus, the restriction endonuclease BbvBI is a true isoschizomer of nuclease BanI.

Bacillus↗
PubMed1991

[BsoAI--a new site specific endonuclease from Bacillus coagulans].

A new site-specific endonuclease was detected in toluene lysates of Bacillus coagulans AUCM B-732 and designated as BcoAI. The enzyme was purified by fractionation of the cell-free extract in the two-phase PEG/dextran system followed by chromatography on DEAE-sepharose and phosphocellulose and shown to be free of nonspecific nucleases and phosphatases. BcoAI has three cleavage sites on lambda DNA, but does not cleave SV40, pBR322 and pUC19 DNA. BcoAI recognizes the sequence 5' CAC decreases GTG 3' on double-stranded DNA and cleaves it as indicated by the arrow to yield blunt-ended DNA fragments. Thus, BcoAI is a true isoschizomer of PmaCI from Pseudomonas maltophila C.

Autoradiography↗
PubMed1988

[The search for strains producing new restriction endonucleases].

The search for restrictases in 154 strains belonging to 104 species of 32 genera of microorganisms has been carried out by the method of rapid toluene assay. In 10 strains the activity of endonucleases specifically fragmenting the DNA of phage lambda in the presence of Mg2+ ions has been detected. Restrictases Pae I and Pae II formed by two Pseudomonas aeruginosa strains have been identified as the true isoschizomers of restriction endonucleases Sph I and Sma I respectively. The results of the screening of restrictase-producing strains indicate that the production of restrictases is widely spread among microorganisms of the genus Bacillus.

Bacteria↗
PubMed1986

[New specific endonucleases PaeI and PaeII from Pseudomonas aeruginosa].

Specific endonuclease activities have been found it two Pseudomonas aeruginosa strains. Isolation and purification of enzymes and determining their specific activities have permitted one to find out that PaeI is an isoshizomer of SphI and digests the sequence 5'-GCATG C-3'. Another isolated enzyme PaeII is an isoshizomer of SmaI and cleaves DNA in a fragment 5'-CCC GGG-3'. The use of PaeI and PaeII enzymes in genetical engineering and their advantages are discussed.

Base Sequence↗
PubMed1986

[Effect of thiol-specific reagents on the activity of PaeI and PaeII restrictases from Pseudomonas aeruginosa].

5,5'-dithiobis-2-nitrobenzoic acid, N-ethylmaleimide, and parachloromercuribenzoate have been demonstrated to inhibit the activity of restrictases PaeI and PaeII from Ps. aeruginosa bacterial cells. Restrictase PaeII was more sensitive to the action of thiol-specific reagents, as compared to PaeI. The minimal concentration of reagents for SH-groups that completely inhibited the activity of restrictases PaeI and PaeII was determined. The protective effect against the inhibitory action of 5,5'-dithiobis-2-nitrobenzoic acid on the activity of PaeII was observed after preincubation of these enzymes with phage lambda DNA and Mg2+ cations. It is suggested that restrictase PaeI and PaeII molecules contain SH-groups, essential for the enzymatic activity. They are believed responsible for restrictase binding with DNA substrate.

Bacteriophage lambda↗
PubMed1978

[Several biological properties of E. coli SK cells].

Escherichia coli SK cells are not colicinogenic, but possess multiple resistance to antibiotics (tetracycline, kanamycin, penicillin, polymyxin, ampicillin). Numerous variations, sensitive to one or several of the antibiotics listed were obtained by cloning the initial culture. Experiments with acridine orange failed to eliminate completely the resistance of E. coli cells to all five of the antibiotics under study. Partial modifications in the spectrum of antibiotic resistance did not influence the host specificity system present in the cells SK. The capacity of restriction and the activity of the methylating enzymes in all the clones under study in the initial strain proved to be the same.

Clone Cells↗
PubMedDate not supplied

[The role of divalent cations in DNA endonucleolysis catalyzed by restrictases].

Electrophoretic analysis of products obtained after hydrolysis of phage lambda DNA by means of restrictase Pae I was carried out after preincubation of DNA or the enzyme with Mg2+ as well as after preincubation of DNA simultaneously with the enzyme and the subsequent addition of the required components into the experimental samples. The analysis showed that Mg2+ were apparently not required for the enzyme-substrate complex formation and caused destabilization of the complex. Restrictase Pae I was in active form when Mg2+ was substituted by Mn2+, Ca2+, Zn2+, Co2+ but not by Cd2+, Cu2+ or Ni2+. Experiments with o-phenanthroline showed that Zn2+ cations are of importance in catalytic activity of restrictase Pae I. Possible functions of Zn2+ in protein-nucleic acids recognition are discussed.

Cations, Divalent↗
PubMedDate not supplied

[Detection of plasmids in the cells of E. coli CK].

Superspiralized coiled plasmide DNA were found in cells E. coli CK. One of plasmides pEco CK-1 had a size 21.2 micron that corresponded to molecular mass 43.7 megadaltons, another plasmide pEco CK-2 with the size 14.2 micron had a molecular weight 29.2 megadaltons. Effective restriction was observed in cross titration using phage PBV-I.CK for E. coli strains carrying R II plasmide and phage PBV-I.R II for E. coli CK cells. The data obtained suggest that the Eco CK type with DNA of host specificity is distinct from hsp II type due to presence of R II and N-15 plasmides.

Coliphages↗
PubMedDate not supplied

[Relations between the condition of growth and activity of DNA-methylases of Mycobacteria butyricum].

Conditions for cultivation of Mycobacteria butiricum were studied. Optimal conditions were selected to maintain maximal rate of DNA-metylase activity keeping of unspecific nuclease activity in cells at a low level. Analyses of plots of the time- dependent DNA methylation by the enzymes, isolated from bacterial preparations cultivated under various conditions (solid and liquid synthetic and organic media with earation and without of it), demonstrated that aeration and organic medium were the deciding conditions responsible for high level of the methylase activity. The shape of plot of DNA methylation by the enzymes from M. butiricum was similar irrespective of the conditions of cultivation--maximal rate of methylation occurred within 2-3 hrs of incubation and was maintained within 22 hrs. The stable content of methylated DNA-acceptor, within long-term periods of incubation, correlated with the low level of nucleases since viscosity of DNA from Cd phage was unaltered after incubation with the enzyme preparation from M. butiricum. The M. butiricum strain appears to be valuable for identification of restrictases.

Bacteriological Techniques↗