• Korean Journal of Microbiology
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• v.24 no.4
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• pp.406-410
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• 1986

The isolation and charateriation of a type II restriction endonuclease from Xanthomonas citri IFO 3835 were described. This enzyme (Xci I endonuclease) is an isoschizomer of Sal I endonuclease recognizing 5'-GTCGAC-3' and cleaving at the site indicated by the arrow. Unlike Sal I endonuclease, Xci I endonuclease requries a NaCl concentration of 50mM for its maximum activity.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.43-51
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• 1993

Mitochondrial DNA(mt DNA) of Mammalian is the circular one which the 16.5K base pairs and show the maternal inheritance. Evolutional speed of nucleotide sequence is very fast. So that polymorphic analysis of mt DNA provide the useful informations to investigate the genetic relations of interspecies. Authors trials were focussed to compare with the polymorphic differences of mitochondrial DNA between Jindo and Japanese mongrel dogs. DNA was extracted from bloods of 21 head of Jindo dogs and 20 head of Japanese dogs and isolated using 10 kinds of restriction endonucleases(Apa I, BamH I, Bgl II, EcoR I, EcoR V, Hinc II. Hind III, Pst I, Sty I, Xba I) and then separated by the agarose gel electrophoresis. After sourthern blotting hybridization was completed using the mtDNA of Japanese mongrel dogs as a probe. Autoradiography was used to compare the polymorphism of mtDNA both dogs. The results obtained were as follows; 1. mt DNA of Jindo dog showed polymorphism resulting cleavage with four kinds of restriction endonuclease, Apa I, EcoR V, Hinc II, Sty I. While in the Japanese mongrel dogs observed the polymorphism in the five kinds of restriction endonuclease supplemented with EcoR I. 2. Compared with both dogs the frequency differences of DNA polymorphism were recognized in the specific restriction endonuclease Apa I. Consequently in the restriction endonuclease Apa I both dogs classified with three types as A, B, C however in the Jindo dogs frequency of C type was 71.5 percent but in Japanese mongrel dogs observed 45 percent in the A type. 3. DNA polymorphism obtained from the use of five kinds of restriction endonuclease were classified with seven types. In Jindo dogs frequency was highest in the type 6 as 71.4 percent but in the Japanese mongrel dogs showed 35 percent in the type 5. 4. Genetic distances calculated by NEI method showed 0.0089 in Jindo dogs and was 0.0094 in the Japanese mongrel dogs.

• Microbiology and Biotechnology Letters
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• v.15 no.5
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• pp.352-355
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• 1987

The isolation and characterization of type II restriction endonuclease from Clostridium thermocellum ATCC 27405 were described. This enzyme (Cth I endonuclease) is an isoschizomer of Bcl I endonuclease recognizing 5'-TGATCA-3'. Cth I endonuclease requires MG$^{2+}$ ion for its activity and is maximally active at PH 1.5 to 10.5 in the Presence of 0 to 10mM NaCl. Cth I endonuclease is heat stable and has an optimum temperature of 6$0^{\circ}C$. The activity of Cth I enzyme is sensitive to dam methylation.

• Korean Journal of Microbiology
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• v.26 no.1
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• pp.1-5
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• 1988

The esolation and characterization of a new type II restriction endounclease, BamI, from Bacellus macerans ATCC 8244 were described. BmaI endonuclease was partially purified by procedures of ammonium sulfate fractionation, DEAE-cellulose and phosphocellulose chromatographies. This enzume recognized one site on pBR322 DNA, two sites on Bluescribe DNA, three sites on $\lambda$DNA and no site on SV 40 DNA. The same cleavage patterns for vareius DNAs as PvuI indicated that BamI is an isoschisomer of PvuI whose recognition sequence is 5'-CGATCG-3'. The optimal pH for the BmaI endonuclease activity was about 7.0 and optimal NaCl concentration was about 100mM. Manganese ion could partially replace magnesium as a cofactor, but calcium could not at all.

• Korean Journal of Microbiology
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• v.32 no.4
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• pp.285-290
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• 1994

About 500 bacterial and fungal strains from a wide variety of natural habitats were screened for a new type II restriction endonuclease. Among the 500 species, we selected one species that produced a new restriction endonuclease. This strain has an optimum temperature of $30^{circ}C$ for growth. Morphological, cultural, and physiological characteristics were examined for identification of the isolated strain J-482. This strain was found to belong to the genus Alcaligenes. The restriction endonuclease was named as AspJI and partially purified from Alcaligenes sp. J-482 by DEAE-Sephadex A-50 column chromatography and gel filtration. Most of other nucleases were removed by the purification steps. The AspJI has a substrate specificity to ${lambda}$ DNA, pBR322 and Adenovirus-2 DNA. For its maximal activity, the isolated enzyme requires $MgCl_2$, which should be at least 12.5 mM and it does not need any other cofactors. It is maximally active in the absence of NaCl and is completely inactivated at 100 mM NaCl. The pH and temperature optima for activity were pH 7.5 and $37^{circ}C$, respectively. The DNA fragments generated by digesting ${lambda}$ DNA, pBR322, and Adenovirus-2 DNA with AspJI were the same as that produced by AatII. This suggests that AspJI is an isoschizomer of AatII.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.30-38
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• 2010

The contribution of a type II restriction-modification system (R-M system) to genome integrity and cell viability was investigated. We established experimental conditions that enabled the achievement of hemimethylated and unmethylated states for the specific bases of the recognition sequences of the host's DNA. To achieve this, we constructed the MboII R-M system containing only one (i.e., M2.MboII) out of two functional MboII methyltransferases found in Moraxella bovis. Using the incomplete R-M system, we were able to perturb the balance between methylation and restriction in an inducible manner. We demonstrate that upon the SOS-induced DNA repair in mitomycin C treated cells, restriction significantly reduces cell viability. Similar results for the well-studied wild-type EcoRI R-M system, expressed constitutively in Escherichia coli, were obtained. Our data provide further insights into the benefits and disadvantages of maintaining of a type II R-M system, highlighting its impact on host cell fitness.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.18-23
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• 1986

A new type II restriction endonuclease, Bdi I, has been isolated from Brenibacterium divaricatum FERM 5948 by procedures of ammonium sulfate fractionation, DEAE-cellulose chromatography and heparin agarose chromatography. The purified Bdi I restriction endonudlease had the same cleavage patterns of Cla I whose recognition sequence is 5' ATCGAT 3'. From the result that ${\lambda}-Cla$ I DNA frahment could be cloned in pBR 322 digested with Bdi I, it has been proven that Bdi I cuts between T and C(5' AT/CGAT3') within the recognition sequence and produces 5'pCG cohesive end. The optimal temperature for the Bdi I restriction endonuclease activity was $37^{\circ}C$, and optimal salt (NaCl) concentration was 50-100 mM.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.208-214
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• 1994

We screened many species from a wide variety of bacterial genera for a new type II restriction endonuclease. The purification and characterization of SolI from a soil isolate, Streptoverticillium olivoverticillatum are described here. The enzyme turned out to be an isoschizomer of BamHI. It recognized the hexanucleotide sequence of 5'-G$\downarrow$GATCC-3' and cleaved as in dicated by the arrow, generating a 4 base 5' extension. Unlike its isoschizomer, BamHI, the activity was sensitive to dam methylation within the recognition sequence. Following ammonium sulfate fractionation of the crude extract, heparin-agarose and Affi-gel Blue column chromatography were employed to purify the enzyme. SolI required at least 0.2 mM of $MgCl_2$ for the cleavage to occur. The enzyme exhibited its maximal activity in the absence of NaCl, but was inhibited completely in the presence of 120 mM NaCl. The pH and temperature optima for activity were pH 8.6 and $40^{\circ}C$, respectively. The molecular weight of SolI was estimated to be 43,000 Da by Superose-12 gel filtraion chromatography.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.180-183
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• 1987

Stu I, type II restriction endonuclease, has been purified to homogeneity from Streptomyces tubercidicus (ATCC 25502), and its catalytic properties have been studied. For the purification of Stu I endonuclease free of nonspecific nucleases, DEAE-Sephadex (A-50), QAE-Sephadex (A-50) and Heparin-agarose column chromatography have been performed after ammonium sulfate fractionation of the crude extract. The enzyme was further purified by gel filtration using Sephadex G-100 column to obtain homogeneous form of protein. The single polypeptide species of Stu I endonuclease has a subunit molecular weight of 34,000 $\pm$ 1,000 daltons as judged by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Stu I endonuclease requires $Mg^{2+}$ ion for its activity and is maximally active at neutral pH (7.0-8.0) in the absence of NaCl.

• KSBB Journal
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• v.11 no.2
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• pp.193-200
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• 1996

In molecular biology, type-II restriction endonuclease, which specifically recognize and cleave DNA at a limited number of sites, have been exploited as a means of characterizing DNA fragments, DNA mapping for genetic engineering. Type-II restriction endonucleases have been found to modulate their substrate specificity under modified conditions such as extreme pH, ionic strength, high enzyme concentration, substitution of metallic cofactors or addition of organic solvents. This study was initiated to investigate the modification of recognition specificity of BamHI according to the different pH and organic solvent under the given buffer condition. The specificity of BamHI is highly depends on the presence of hydrophobicity (LogP: partition coefficient) and pH of reaction solution. The specificity of BamHI is changed in range of LogP -1.03∼-1.35(at pH 7.5), -1.03∼-2.5 (at pH 8.0), -0.75∼-0.25(at pH 8.5), 0.32∼-2.5(at pH 8.9), respectively. Alteration of specificity appears in lower concentration of organic solvent when the reaction occurs in more alkali pH. For example, in DMSO solution, alteration of specificity appears in 20% concentration at pH 7.5 but in 4% concentration at pH 8.9.