• BMB Reports
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• v.31 no.2
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• pp.149-155
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• 1998

The N199H variant of the EcoRI endonuclease has about twice the catalytic activity of the wild-type. A comparison of their biochemical characteristics, using synthetic oligonucleotides 5'-dAAAACTTAAGAAAAAAAAAAA-3' (KA) and 5'-dTTTTTGAATTCTTTTTTTTTT-3' (KT), helps to define the cleavage reaction pathway of these enzymes. Both EcoRI and EcoRI variant N199H were found to cleave singlestranded KA or KT about three times faster than the double-stranded forms, although the KT oligonucleotide was more susceptible. Using the ssDNA substrate in kinetic analyses, lower $K_m$ values were obtained for the N199H variant than for the wild-type at low (50 mM), as well as high (200 mM), sodium chloride concentrations. This difference between the endonucleases is attributed to a grealter accessibility for tbe substrate by the variant, and also a higher affinity for the DNA backbone. It also appears that the relative activities of the two enzymes, particularly at high ionic strength, are proportional to their populations in the monomeric enzyme form. That is, according to gel filtration data, half of the N199H molecules exist as monomers in 200 mM NaCl, whereas those of the wild-type are mainly dimeric. Consequently, the Asp199 residue of the EcoRI endonuclease may be implicated in the protein-protein interaction leading to dimerization, as well as in coupling to DNA substrates. In summary, it is proposed that active monomeric endonuclease molecules, derived from the dimeric enzyme, recognize and form a complex with a single stranded form of the DNA substrate, which then undergoes nucleophilic substitution and cleavage.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.63-77
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• 2006

The research aim is to classify biotope types of rural eco-villages designed by ministry of environment and analyze landscape ecological characteristics of them. This information would provide information on eco-villages' potential and specific needs to improve landscape ecological structure of eco-villages. Two eco-villages, designated by ministry of environment, in Yoocheon-ri and Sanduk-ri were selected and the landscape ecological metrics used in this study were Area, Shannon diversity index, Shape index, Distance index. The results are as follows. 1) There were five biotope types in large-scale classification, 13 biotope types m Sanduk-ri and 9 biotope types in Yoocheon-ri in middle-scale classification, 31 biotope types in Sanduk-ri and 24 biotope types in Yoocheon-ri in small-scale classification. 2) In the case of area, artificial biotope types, such as artificial forest, agricultural irrigation canal, wet paddy, dry paddy and residential area, covered more than 80% of total area. However, natural biotope types, such as natural forest, river, reservoir, covered just more than 10% of total area. In details, an orchard (26.69%) was the dominant biotope type, followed by artificial forest (19.10%) in Sanduk-ri and the first most abundant biotope type was artificial forest (49.71%), followed by wet paddy (15.95%) in Yoocheon-ri. 3) The result of Shannon diversity index indicated that Sanduk-ri (2.158) had more heterogeneity landscape, rather than Yoocheon-ri (2.051). 4) In the case of shape index, road (13.09) had more complex and irregular shape than either agricultural irrigation canal (3.35) or artificial forest (2.46) in Sanduk-ri. Road (6.52) was also the most irregular biotope shape, followed by river (5.70) and agricultural irrigation canal (4.78) in Yoocheon-ri. 5) Mean Nearest-neighbour Distance (MND) was smallest in wet paddy and dry paddy biotope types in the two study area, suggesting that these biotope types were concentrated within these study areas. From the result, this research suggested information to protect and improve biotopes of eco-villages in the landscape ecological terms. To achieve this improvement plan, there should be strong support by ministry of environment and local governments.

• Journal of Plant Biology
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• v.32 no.2
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• pp.79-87
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• 1989

Southern hybridization of genomic DNAs with radioactively labeled cDNA of tomato proteinase inhibitor II revealed that proteinase inhibitor II proteins in potato plants are encoded by a family of about 10 related sequences. Screening of potato EcoRI genomic library with the cDNA resulted in isolation of 13 recombinant phage clones which carry 3 different genomic regions. Of these clones, clones 8, 18, and 39 were subjected to restriction mapping and subcloning. Further characterization of the subclones of clones 8, 18 and 39 indicated that two inhibitor II genes are present on a 8.0 kb EcoRI fragment of clone 8, one on 3.3 and 0.8 kb EcoRI fragments of clone 18 and two genes on a 13.5 kb EcoRI fragment of clone 39.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.231-235
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• 1998

We have introduced a genetic assay to study the existence of intramolecular triplexes in Escherichia coli. A plasmid containing the gene that encodes a temperature-sensitive EcoRI methylase was cotransformed with different plasmids containing inserts, $(G)_9AATTC(G)_9$ and $(GAA)_9TTC(GAA)_8$, that are able to form intramolecular triplexes in vitro. Inhibition of methylation in vivo was found for $(G)_9AATTC(G)_9$ and $(GAA)_9TTC(GAA)_8$, suggesting that the pur pyr sequences adopt unusual strucures in E. coli. In addition, experiments using two dimensional gel electrophoresis confirmed that intramolecular triplexes are formed for the pur pyr sequences under negative supercoiling. These results demonstrate the existence of intramolecular triplexes in E. coli.

• Journal of fish pathology
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• v.8 no.1
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• pp.37-46
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• 1995

The amino acid analysis of polyhedrin protein and nucleotide sequence of polyhedrin gene in H. cunea nuclear polyhedrosis virus (HcNPV) genome have been studied. Polyhedrin had three polypeptide bands in SDS - polyactylamide gel electrophoresis. The major polypeptide had a molecular weight of 25 kd. The polyhedrin was composed of 17 different amino acids. HcNPV DNA was digested with EcoRI restriction enzyme and hybridized with ($\alpha^{32}P$) -labelled AcNPV polyhedrin gene cDNA. The polyhedrin gene was located on the fragment of EcoRI-H. The EcoRI - H fragment containing polyhedrin gene was cloned into the EcoRI site of pUC8 vector which was confirmed with southern blotting, and the recombinant plasmid containg polyhedrin gene was designated as hPE-H. The promoter region of polyhedrin genomic DNA was sequenced. The sequences identified as the TATA box was found at the 5' flanking region of the polyhedrin genomic DNA approximately -79 bp upstream from the transcriptional start site. But CAAT-like box was not shown near the TATA-like box in the polyhedrin gene. Four tandem repeats with the sequence 5' -CTAATAT-3' and 5'-TAAATAA-3' were found between -141 and -108 or -83 upstream and -52 bp downstream from the translation start site. About -141 bp region upstream from the translational start site was highly AT (78%) rich. The coding region for the polyhedrin starts and ends with ATG and TAA, respectively.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.160-164
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• 1989

A 5.7Kb EcoRI fragment containing alkaline amylase gene of Bacillus sp. AL-8 obtained in the previons experiment (10) was transformed in B. subtilis via plasmid pUB110. The enzymatic proper-ties of the amylase produced by the transformants were Identical to those of the donor strain. Thus, the alkaline amylase activity from the transformant was maximum at pH 10 and 5$0^{\circ}C$. And the enzyme was very stable over the ranges of alkaline pH. In order to determine the location of the alkaline amylase gene within the 5.7Kb DNA fragment, the fragment was subcloned in E. coli. It was found that the alkaline amylase gene was located k EcoRI fragment of 3.7Kb.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.98-102
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• 1990

A strain of Erwinia spp. was selected from the soil for the production of bacteriocin to the root rot plant pathogen. Bacteriocin producing gene was not located on plasmid but on chromosome. Genomic library of Erwinia spp. were made by using pLAFR 3 as a vector system for cloning of the gene. It was been cloned and expressed in E. coli DH 5 . Bacteriocin producing colony was composed of pLAFR 3 vector and 3.0 kb EcoRI fragment of Erwinia spp. ehromosomal DNA. The inserted fragment (3.0 kb) was possessed a EcoRI and BarnHI restriction sites.

• Journal of fish pathology
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• v.8 no.1
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• pp.31-36
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• 1995

Hc nuclear polyhedrosis virus DNA genome was digested with EcoRI endonuclease, these partial fragments were recombined into the pUC8 plasmid vector and transformed in E. coli JM 83 cell. The genome DNA has 24 EcoRI fragments and 12 fragments of them were subcloned. The four recombinants were named as eNP-O, eNP-Q, eNP-R and eNP-S. The expression of foregin gene of the recombinants was investigated by analysing protein patterns on the SDS-PAGE. The eNP-O, eNP-Q and eNP-R were expressed a different weight of protein as comparision with potypeptide bands of E. coli JM 83 host cell.

• Journal of Environmental Impact Assessment
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• v.8 no.1
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• pp.141-146
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• 1999

This paper proposes the planning and design of the Eco-village centering around Chindo-ri, Muju-kun. The Eco-village project has three basic objects the Eco-village residents' lives adapting to ecological principles such as regeneration and circulation, life agricultural techniques based on organic cycle, and residents' harmonious lives with the surrounding nature. For constructing of the Eco-village, first, the subject area was analyzed in terms of the natural and cultural environment and then, on this analytic ground the concrete concept and the specific plan were set up. The following details also should be considered: the scale of the residential household, the population, the space arrangement of the village, the material cycling structure, the waste treatment, the purification of the sewage, the energy supply, the landscape architecture, the production activity, the conservation of the ecosystem and so on.

• Biomedical Science Letters
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• v.8 no.2
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• pp.77-82
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• 2002

Ten Listeria monocytogenes were isolated from clinical specimens and mussels, and their physio-biochemical characters were compared with the type strains. Ribotyping was used as a taxonomic tool to determine molecular epidemiological marker. Chromosomal DNA was cleaved with restriction enzymes HindIII and EcoRI. The fragment were subjected to Southern blot hybridization with 165 rDNA from B. subtilis by PCR. EcoRI patterns of Listeria strains showed 6 to 8 bands ranging from 0.75 kb to 11 kb band and they were classified into 6 groups. In comparison, HindIII patterns revealed that 5 to 7 bands ranging from 2.75 kb to 7.75 kb band and they classified into 5 groups. The various patterns of Listeria strains were observed within genus, species and isolated sources. 165 rRNA gene restriction patterns (ribotyping) are useful in epidemiological and taxonomic study.