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L A Zheleznaia

Publications and source records attributed to L A Zheleznaia.

At least 19 recordsLinked to original sources
PubMed1996

[Novel site-specific endonuclease from Acinetobacter species M strain].

Site-specific endonuclease R. AspMI was isolated and purified to apparent functional homogeneity from Acinetobacter species (strain M). The enzyme recognizes symmetrical DNA sequence 5'-AGG decreases CCT-3' and cleaves it at the site indicated by the arrow forming blind DNA ends. The endonuclease is an isoschizomer of the StuI endonuclease. Cleavage of the DNA site was inhibited by dcm-methylation. AspMI is approximately equal to 30 kD monomer.

Acinetobacter↗
PubMed1996

[Two site-specific endonucleases from the thermophilic OV Bacillus species strain].

Two site-specific endonucleases, BspOVI and BspOVII, were isolated from a thermophilic strain Bacillus species OV. The activities of both enzymes are maximal at 48 degrees C and do not depend on ATP and S-adenosyl-L-methionine. BspOVI recognizes the sequence [sequence: see text] and cleaves it as indicated by arrows. Thus, BspOVI is a IIN-subclass endonuclease isoshizomer of Eam1105I. BspOVI is very stable during storage. The enzyme can be used for direct T/A cloning of PCR products. BspOVII recognizes and cleaves the sequence [sequence: see text]; thus, BspOVII is an isoshizomer of CIaI. The cleavage by BspOVII is blocked by dam methylation of adenine inside the recognition site.

Bacillus↗
PubMed1996

[Site-specific endonuclease BspR7I from thermophilic strain of Bacillus sp. R7].

A site-specific endonuclease which recognizes the sequence 5'-CCTNAGG-3' was purified to homogeneity from the thermophilic strain Bacillus sp. R7. The endonuclease (BspR7I) is monomeric protein with an apparent molecular weight of 37 kD. The enzyme is active over a wide range of NaCl concentrations, pH, and temperatures. BspR7I cleaves DNA substrates according to the scheme: 5'-CC decreases TNAGG-3' 3'-GGANT increases CC-5', hence the endonuclease represents an isoschizomer of Bsu361.

Bacillus↗
PubMed1995

[Site-specific endonuclease BspKT8 from the thermophilic strain KT8 of Bacillus species].

A site-specific endonuclease capable of recognizing the sequence 5'-AAGCTT-3' was detected and purified to homogeneity from the thermophilic strain of Bacillus species KT8. The endonuclease has a molecular mass of 34 kDa and is found in solution in a monomeric form. The activity of BspKT8 does not depend on ATP and is not stimulated by S-adenosyl-L-methionine. The enzyme displays the highest activity with a broad range of temperatures (37 degrees-48 degrees C). Since DNA cleavage occurs in accordance with the scheme: [formula: see text] the enzyme can be assigned to the class-II of restriction endonucleases and represents an isoschizomer of HindIII.

Bacillus↗
PubMed1995

[A method of selective PCR-amplification of genomic DNA fragments (SAGF method)].

A method for separating into definite sets of a complex mixture of fragments obtained by DNA cleavage with IIS- or IIN-types of restriction endonucleases producing single-stranded termini of different sequences at the fragment ends has been developed. The method is based on the ligation of short double-stranded adapters with single-stranded termini complementary to the termini of a selected set of fragments followed by PCR-amplification with the primer which represents a strand of the adapters. Using endonucleases BcoKI and Bli7361 recognizing sequences CTCTTC and GGTCTC and producing three- and four-nucleotide 5'-termini, respectively, it has been shown that amplification of a set of fragments occurs only when the adapters are attached to DNA fragments with DNA-ligase. Several applications of the SAGF-method are suggested: for obtaining individual bands in DNA fingerprinting; for reducing the kinetic complexity of DNA in the representational difference analysis (RDA method) of complex genomes; for cataloguing DNA fragments, and for constructing physical genomic maps.

Animals↗
PubMed1995

[Site-specific endonuclease and methylase from thermophilic bacteria of Bacillus species IS4].

The site-specific endonuclease R . BspIS4I and methylase M . BspIS4I have been isolated and purified to functional purity from the thermophilic strain of Bacillus species IS4. R . BspIS4I recognizes sequence [sequence: see text] on the DNA and cleaves it as indicated by the arrows to form single-stranded 4-nucleotide 5'-protruding termini. The enzyme is an isoschizomer of BbvII. M . BspIS4I is related to adenine-specific methylase.

Bacillus↗
PubMed1995

[A new site-specific endonuclease from Bacillus species ST5].

A site-specific endonuclease R.BspST5I has been isolated in a functionally pure state from the thermophilic strain of Bacillus species ST5. The enzyme recognizes sequence 5'-GCATC-3' on the DNA and splits it at a distance of five nucleotides from the 3'-end of the recognition site as well as at distances of nine or ten nucleotides at the complementary filament depending on the hydrolyzed sequence of the DNA. The enzyme is a isomer of endonuclease SfaNI from Streptococcus faecalis ND547.

Bacillus↗
PubMed1994

[Nucleotide sequence of the Escherichia coli B38 flagellin gene].

The fliC gene of the E. coli B38 flagellin has been cloned and its nucleotide sequence determined using the terminator method. According to the sequencing data, the flagellin contains 565 amino acid residues which exceeds by 65 residues the number of amino acid residues in the earlier decoded E. coli K12 flagellin. Strong homology was observed in the two flagellins among the 160 initial and 89 tail-ended residues, whereas the central, variable parts showed no homology. Similar to the K12 flagellin, the B38 flagellin has no serines, cysteines or tryptophans. The variable part of the fliC E. coli B38 gene contains a Chi-site which initiates the genetic recombination in E. coli and related species.

Amino Acid Sequence↗
PubMed1994

[A new site specific endonuclease-methylase from a thermophilic strain of Bacillus species LU11].

A new site-specific endonuclease BspLU11III was purified to homogeneity from a thermophilic strain Bacillus species LU11. BspLU11III recognizes the 5'-GGGAC-3' sequence on the double-stranded DNA and cleaves the 10/14 and 11/15 nucleotides in different strands away from the recognition site. The enzyme exists in solution as a monomer with a molecular mass of about 93 kDa. When incubated with S-adenosyl-L-methionine, BspLU11III displays a DNA-methyltransferase activity. The adenine residue is methylated inside the recognition site 5'-GGGAC-3' in the only strand. The restriction activity does not change in the presence of ATP but is stimulated by 80 microM S-adenosyl-L-methionine (4-fold). Magnesium cations are needed for the restriction activity. Sodium chloride stimulates the "star" activity of BspLU11III. According to its properties, BspLU11III can be classified as a type IV endonuclease.

Bacillus↗
PubMed1994

[A new site-specific endonuclease and methylase from a thermophilic strain of Bacillus species KT6].

The site-specific endonuclease R.BspKT6I and the cognate site-specific methylase M.BspKT6I have been isolated from the thermophilic strain of Bacillus species KT6 using gel-filtration on Sephadex G100 followed by chromatography on heparin-Sepharose and hydroxyapatite. Endonuclease BspKT6I is an isomer but not an isoschizomer of Sau3AI and MboI. It recognized on the DNA molecule the GAT decreases C sequence and cleaves it; however, unlike Sau3AI and MboI it produces 3'-protruding dinucleotides. The site cleavage is inhibited by dam-methylation. The sticky ends resulting from the BspKT6I cleavage are identical and complementary to the ends formed after the PvuI cleavage. The isolated from the B. species KT6 methylase protects the DNA from subsequent cleavage by BspKT6I. Adenine is a methylated base.

Bacillus↗
PubMed1994

[A new site-specific endonuclease BspKT51].

The new site-specific endonuclease BspKT5I free from interfering impurities has been isolated from thermophilic soil bacteria Bacillus species KT5 by successive chromatography on blue agarose, hydroxyapatite and heparin-Sepharose. BspKT5I on double-stranded DNA recognizes the sequence 5'-CTGAAG16N decreases 3'-GACTTC14N increases and cleaves the DNA at the recognition site as indicated by the arrows to form dinucleotide 3'-protruding termini. The isolated endonuclease is an isoschisomer of Eco57I. However, unlike Eco57I, it is not stimulated by S-adenosylmethionine (SAM) and can therefore be related to subclass IIs but not to IV, as Eco57I. In addition, endonuclease BspKT5I, unlike Eco57I, has no methylase activity.

Bacillus↗
PubMed1993

[Two site-specific endonucleases from the thermophilic strain Bacillus species LU11].

Upon screening of natural strains of thermophilic bacteria, a strain has been found which contains two restriction endonucleases. One of those, BspLU11II, is an isoschizomer of XbaI, while the other one, BspLU11I, recognizes the new palindromic sequence 5'-A decreases CATGT-3' and cleaves it as indicated by the arrow. Functionally pure enzymes were obtained by stepwise chromatography with blueagarose, hydroxyapatite and heparin-Sepharose. The restriction endonuclease BspLU11I produces sticky ends identical to those produced by the restriction endonuclease NcoI; hence a combination of BspLU11I and NcoI can be used for enzymatic selection of recombinant DNA. The recognition sequence of BspLU11I contains the ATG codon and can be used to construct expression vectors for chemically synthesized genes.

Bacillus↗
PubMed1993

[Isolation and properties of site-specific endonuclease BspTS514I from the thermophilic bacteria Bacillus species TS514].

New site-specific endonucleases BspBS31I, BstBS32I, BspIS41, BstTS5I, BspTS514I were isolated from five thermophilic soil bacteria Bacillus sp. BS31, B. stearothermophilus BS32, Bacillus sp. IS4, B. stearothermophilus TS5, Bacillus sp. TS514. The enzymes are isoschizomers of the restriction endonuclease BbvII. Endonuclease BspTS514I was obtained pure from interfering contaminations by two consecutive chromatographies on blue agarose and hydroxyapatite. The enzyme exhibits a maximal activity at 55 degrees C in 10 mM tris-HCl (pH 9.2), 10 mM MgCl2 and 50 mM NaCl.

Bacillus↗
PubMed1993

[Isolation of site-specific endonucleases and methylases from Bacillus cereus 83].

The site-specific endonuclease R Bce83I and methylase M Bce83I were isolated from Bacillus cereus 83 by three consecutive chromatographies on blue agarose, hydroxyapatite and heparin-Sepharose. R Bce83I recognizes [formula: see text] sequences on the DNA and cleaves the DNA as indicated by the arrows. The endonuclease is stimulated by S-adenosyl-L-methionine and may consequently be referred to type IV restriction enzymes.

Bacillus cereus↗
PubMed1993

[New site site-specific endonuclease and methylase from Bacillus licheniformis 736].

The site-specific endonuclease R Bli736I and methylase M Bli736I have been isolated from the Bacillus licheniformis strain 736 by blue-agarose, hydroxyapatite-Ultragel and heparin-Sepharose chromatography. The enzymes are free from interfering impurities. R Bli736I recognizes the 5'-GGTCTCN-3' decreases and decreases 5'-NNNNNGAGACC-3' sequences on the DNA and cleaves the DNA as indicated by arrows to form single-stranded 4-nucleotide 5'-protruding termini. This enzyme is an isoschizomer of Eco3II isolated from E. coli.

Bacillus↗
PubMed1992

[BspLS2I--a new site-specific endonuclease from the thermophilic bacteria Bacillus species LS2].

A new restriction endonuclease BspLS2I was isolated from the thermophilic bacterium Bacillus species LS2 and purified by blue sepharose and hydroxyapatite chromatographies. The enzyme is an isoschizomer of SduI from Streptococcus durans. BspLS2I recognizes the sequence 5' G(G/A/T)GC(C/T/A) decreases C 3' on double-stranded DNA and cleaves it is indicated by the arrow to yield sticky-ended DNA fragments. Maximum catalytic activity of endonuclease was found in 10 mM tris-HCl (pH 7.9) in the presence of 15-30 mM MgCl2 at 50 degrees C. The phage T4 glucosylated DNA is not cleaved by the enzyme.

Bacillus↗