• YAKHAK HOEJI
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• v.39 no.3
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• pp.276-282
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• 1995

Compared to the first and second-generation cephalosporins, the third-generation cephalosporins are remarkably stable against hydrolysis by the $\beta$-lactamases produced by aerobic gram-negative bacilli, such as Enterobacteriaceae. Among these bacteria, the most prevalent plasmid-encoded $\beta$-lactamase is TEM-1 $\beta$-lactamase belonging to class A or group 2b. This enzyme is produced constitutively and is principally active against peniciflins and old cephalosporins rather than third-generafion cephalosporins, carbapenems and mmobactams. However, new TEM type $\beta$-lactamases including TEM-9 and TEM-12 evolved through point mutations in a gene encoding $\beta$-lactamase have been discovered from patients during chemotherapy. These $\beta$-lactamases are known to be capable of hydrolyzing most of the third-generatim cephalosporins. To study the prevalence of $\beta$-lactamases from clinical isolates collected in Korea. the minimal inhibitory concentratims(MICs) of several third-generation cephalosporins against 628 clinical isolates were determined by agar dilution methods, and $\beta$-lactamas-producing bacteria were isolated by use of cefinase disc. By polymerase chain reaction (PCR) method, clinical isolates harboring a gene for TEM type $\beta$-lactamase were identified among the $\beta$-lactamase producing strains. Twentiy three percent of the clinical isolates was resistant to the thirdgeneration cephalosporins, and more than 90% of resistant cells produced various $\beta$-lactamases. TFM type $\beta$-lactamases were dominant in gram-negative bacilli, such as Escherichia coli, Klebsiella pneumoniae, Enterobacter species. These results suggest the necessity of the development of new cephalosporins which are stable against $\beta$-lactamases like TEM.

• Korean Journal of Microbiology
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• v.41 no.4
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• pp.287-292
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• 2005

The cyanobacterial diversity was analyzed by restriction fragment length polymorphism (RFLP) of PCR-amplified rpcBA-Intergenic Spacer (IGS) genes and cpcBA-IGS gene sequencing with a sample collected at Chuso-ri in Daechung Reservoir on March 15, 2005, The Shannon-Weiner diversity index was 0.65, indicating that the cyanobacterial community structure was simple. PCR-RFLP profiles obtained were Phormidium spp. (58 clones), Anabaena spp. (14 clones), Microcystis spp. (4 clones), Spirulina sp. (1 clone) and uncultured cyanobacteria (2 clones). The PCR-RFLP of cpcBA-IGS revealed that Phormidium spp. and Anabaena spp. dominated in the invested sample. As a consequence, it seems that the analysis of functional genes such as cpcBA-IGS can be used for the species identification and community analysis of cyanobacteria.

• Journal of Practical Agriculture & Fisheries Research
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• v.24 no.3
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• pp.5-14
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• 2022

Trichoderma is known as pathogen caused serious green mold disease on commercial production. T. pleuroti and T. pleuroticola were common species in various mushroom media. Many strains of T. pleuroti, known as aggressive species causing major economic losses in Korea, showed benomyl resistance. Accurate identification and detection of Trichoderma species associated with oyster mushrooms is very important for disease control. We developed species-specific primers for T. pleuroticola, T. pleuroti, T. harzianum, and T. atroviride based on species-specific fragments isolated from amplified fragment length polymorphism analysis. PCR products corresponding to the predicted fragment of 500bp, 230bp, 180bp, and 410bp were amplified from T. pleuroticola, T. pleuroti, T. harzianum, and T. atroviride, respectively. Multiplex PCR assay using species-specific primers quickly and accurately identified and detected T. pleuroti from mushroom media in which various species co-exist. Our results can be useful for the effective control of mushroom disease.

• Journal of Animal Science and Technology
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• v.50 no.6
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• pp.753-762
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• 2008

The primers for RT-PCR and RACE-PCR were designed by aligning the pig genomic sequence and the human complement factor B(CFB) coding sequence(CDS) from the GenBank. Each PCR product was amplified in pig cDNA and sequencing was carried out. The CDS length of pig CFB gene was determined to be 2298 bp. In addition, the pig CDS was more longer than human and mouse orthologs because of insertion and deletion. The identities of porcine nucleotide sequences with those of human and mice were 84% and 80%, and the identities of amino acids were 79% to 77%, respectively. Three complement control protein(CCP) domains, one Von Willebrand factor A(VWFA) domain and a serine protease domain, that are revealed typically in mammals, were found in the pig CFB gene. Based on the CDSs determined, the primers were designed in intron regions for amplification of entire length of exons. In amplification and direct sequencing with genomic DNAs of six pig breeds, three cSNPs(coding single nucleotide polymorphisms) were identified and verified as missense mutations. Using the Multiplex-ARMS method, we genotyped and verified the mutations identified from direct sequencing. To demonstrate recrudescence, we performed both direct sequencing and Multiplex-ARMS with two randomly selected DNA samples. The genotype of each sample exhibited the same results using both methods. Therefore, three cSNPs were identified from pig CFB gene and that can be used for haplotype analysis of the swine leukocyte antigen(SLA) class III region. Moreover, the results indicate that the Multiplex-ARMS method should be powerful for genotyping of genes in the SLA region.

• Research in Plant Disease
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• v.19 no.4
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• pp.326-330
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• 2013

During the 2012 growing season, 154 leaf samples were collected from sweet cherry trees in Hwaseong, Pyeongtaek, Gyeongju, Kimcheon, Daegu, Yeongju and Eumseong and tested for the presence of Cherry green ring mottle virus (CGRMV). PCR products of the expected size (807 bp) were obtained from 6 samples. The PCR products were cloned and sequenced. The nucleotide sequences of the clones showed over 88% identities to published coat protein sequences of CGRMV isolates in the GenBank database. The sequences of CGRMV isolates, CGR-KO 1-6 shared 98.8 to 99.8% nucleotide and 99.6 to 100% amino acid similarities. Phylogenetic analysis indicated that the Korean CGRMV isolates belong to the group II of CGRMV coat protein genes. The CGRMV infected sweet cherry trees were also tested for Apple chlorotic leaf spot virus (ACLSV), Apple mosaic virus (ApMV), Cherry necrotic rusty mottle virus (CNRMV), Cherry mottle leaf virus (CMLV), Cherry rasp leaf virus (CRLV), Cherry leafroll virus (CLRV), Cherry virus A (CVA), Little cherry virus 1 (LChV1), Prune dwarf virus (PDV) and Prunus necrotic ringspot virus (PNRSV) by RT-PCR. All of the tested trees were also infected with ACLSV.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.58-65
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• 1996

This experiment was carried out to evaluate the effect of sublethal doses of BPMC, etofenprox, and buprofezin on N. lugens. and its predator C. lividipennis. Buprofezin was found to be the most toxic to N. lugens and the most safe to C. lividipennis among the three insecticides, based on LD50 values. Selective toxicity index calculated by dividing LDSo value of C. lividipennis by that of N. lugens indicated that buprofezin was very safe to C. lividipennis, showing selective toxicity of 2703.3. Longevity and fecundity of N. lugens treated with LDIU and LDm of buprofezin and BPMC were not significantly different with those of untreated brown planthoppers. However, egg hatchability' of N. lugens was greatly reduced when treated with LDm of buprofezin, having the highest inhibition rate of 17.7%. Hatchability of eggs from insects treated with BPMC was similar to that of control. The oviposited peak of treated hoppers appeared late as compared to the untreated which showed the peak at early part of the ovipositional period. The longevity and fecundity of C. lividipennis treated with BPMC were significantly reduced as compared with the untreated. Etofenprox also induced fecundity reduction when treated with LDlo, and LDm. However, C. lividipennis treated with sublethal doses of buprofezin showed no redution in logevity and fecundity. From these results, it may be said that buprofezin can be used to control brown planthopper without disrupting of C. lividipennis population in the rice field.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.328-338
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• 1998

Porphyromonas endodontalis, an anaerobic Gram negative cocobacillus which was known to be associated with the infected root canals and periapical lesions, is very difficult to culture and to detect by the traditional method in that it requires much time to induce the specific black pigmentation, and it is very sensitive to oxygen and the antibiotics added in the culture medium. In this study, the nucleotide sequences of the 'probe h' (0.73kb), one of the specific DNA probes top. endodontalis (ATCC 35406) which had been developed by our department, was determined and then a pair of primers for PCR amplification was fabricated to identify P. endodontalis. The plasmids containing 'probe h' were purified by $Wizard^{TM}$ Midipreps DNA Purification System (Promega Corp.), and the nucleotide sequences of the 'probe h' were determined by the dideoxy chain termination method using TaqTrack Sequencing System (Promega Corp.) and detected by fluorescent labelling method. The sense/antisense PCR primers were designed with computer software (Lasergene, DNASTAR Ind. PCR was done with a programmable GeneAmp PCR System 2400 (Perkin Elmer-Cetus Co.). Each sample containing the whole genomic DNA of P. endodontalis and other black-pigmented Bacteroides was itailly denatured at $94^{\circ}C$ for 5 min and then subjected to 30 cycles, each of them consisting of 60s at $94^{\circ}C$, 60s at $60^{\circ}C$, and 90s. at $72^{\circ}C$. The amplified DNA was resolved electrophoretically in a 1.0 % agarose gel in 1X TAE buffer, stained with EtBr, and photographed on a UV transilluminator. The results were as follows : 1. The nucleotide sequences of 'probe h' (743 base pairs) were obtained by dideoxy chain termination method, and from that results the specific primers to P. endodontalis (ATCC 35406), 'Primer H1/ Primer H2', were designed. 2. It has been found that 'Primer H1/H2' could detect P. endodontalis (ATCC 35406) using PCR. 3. The PCR system with this primers may be a powerful technique to amplify the specific sequences of 'probe h' of P. endodontalis (ATCC 35406) that produce distinct identification of it from other black-pigmented Bacteroides, and this could help us to determine the nature of periapical disease.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.187-190
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• 2012

Various koji were prepared by fungi isolated from traditional nuruk and their quality characteristics were investigated. Acidity and saccharification power of their koji were ranged in 5.0~6.8 and 128sp~241sp. Nine fungi which were showed good quality and sensory evaluation were identified by analysis of their nucleotide sequences with PCR-amplified 18S rDNA internal transcribed spacer-1(ITS-1) and ITS-4 genes. Among them, six strains were identified as Aspergillus oryzae and the other strains were identified as Mycocladus corymbiferus, Rhizo-pus oryzae, Lichtheimia corymbifera.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.333-338
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• 2008

Computational analysis of partial rpoB gene sequence (777 bp) was done in this study to identify B. anthracis and its closely related species B. cereus and B. thuringiensis. Sequence data including 17 B. anthracis strains, 9 B. cereus strains, and 7 B. thuringiensis strains were obtained by searching databases. Those sequences were aligned and used for other computational analysis. B. anthracis strains were identificated by in silico restriction enzyme digestion. B. cereus and B. thuringiensis were not segregated by this method. Those sequencing and BLAST search were required to distinguish the two. In actual identification tests, B. anthracis strains could be identified by PCR-RFLP, and B. cereus and B. thuringiensis strains were distinguished by BLAST search with reliable e-value. In this study fast and accurate method for identifying three Bacillus species, and flow chart of identification were developed.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.523-530
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• 2014

One juvenile raptor which was not able to be identified due to its head damage was discovered on a roadside in Janggok-ri, Jori-eup, Paju on 28th June, 2011. The species was identified by DNA barcoding. After polymerase chain reaction (PCR) of the mitochondrial cytochrome c oxidase subunit I gene (COI), we obtained 695 bp sequences. We analyzed the obtained COI sequence with similar sequences from the BOLD systems and BLAST of the NCBI Genbank, and discovered that its sequence showed 100 % similarity values with the one of the five gray-faced buzzards which were previously researched. In addition, it was confirmed to be a female through sex determination using DNA. Such results are important information as it confirms the breeding of the gray-faced buzzards for the first time in 43 years since its breeding was last recorded in 1968, in Paju. Wildlife rescue center needs to work with adjacent consigned registration and preservation institutions when carcass of wild animals is collected or DNA samples are obtained for more accurate both species and sex identification through a systematic management system in the future. Furthermore, the obtained DNA sample of the gray-faced buzzard and COI gene, DNA barcode, could be used as reference standards for similar researches in the future.