• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.76-88
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• 2004

The purpose of this study was to investigate the distribution of Enterococci isolated from clinical specimens, and identify the aspect of antibiotic susceptibility and analyze the genetic difference by executing Rep-PCR over the strains resistant to aminoglycoside-typed antibiotics. From an assortment of the clinical specimens, 100 strains were isolated. The collection consisted of 49 strains of E. faecalis, 34 strains of E. faecium, 9 strains of E. avium, 4 strains of E. gallinarum, 3 strains of E. casseliflavus, and 1 strain of E. hirae. Ninety five were isolated from inpatients, and five strains were isolated from outpatient. Most of the E. faecalis and E. faecium were originated from urine, pus, and sputum. Most Enterococci showed 80% resistance to the cephalosprin-typed antibiotics. E. faecium showed the high resistance to all the antibiotic substances. One tenths of Enterococci showed the resistance to vancomycin. And also, most Enterococci showed the high resistance to amikacin and gentamicin as aminoglycoside-typed antibiotics. Genetic diversity of the resistant strains to aminoglycoside estimated using Rep-PCR was not significanty different.

• The Plant Pathology Journal
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• v.29 no.2
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• pp.125-135
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• 2013

In agro-ecosystems worldwide, some of the most important and devastating diseases are caused by soil-borne necrotrophic fungal pathogens, against which crop plants generally lack genetic resistance. However, plants have evolved approaches to protect themselves against pathogens by stimulating and supporting specific groups of beneficial microorganisms that have the ability to protect either by direct inhibition of the pathogen or by inducing resistance mechanisms in the plant. One of the best examples of protection of plant roots by antagonistic microbes occurs in soils that are suppressive to take-all disease of wheat. Take-all, caused by Gaeumannomyces graminis var. tritici, is the most economically important root disease of wheat worldwide. Take-all decline (TAD) is the spontaneous decline in incidence and severity of disease after a severe outbreak of take-all during continuous wheat or barley monoculture. TAD occurs worldwide, and in the United States and The Netherlands it results from a build-up of populations of 2,4-diacetylphloroglucinol (2,4-DAPG)-producing fluorescent Pseudomonas spp. during wheat monoculture. The antibiotic 2,4-DAPG has a broad spectrum of activity and is especially active against the take-all pathogen. Based on genotype analysis by repetitive sequence-based-PCR analysis and restriction fragment length polymorphism of phlD, a key 2,4-DAPG biosynthesis gene, at least 22 genotypes of 2,4-DAPG producing fluorescent Pseudomonas spp. have been described worldwide. In this review, we provide an overview of G. graminis var. tritici, the take-all disease, Pseudomonas biocontrol agents, and mechanism of disease suppression.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.221-231
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• 2016

Microsatellites, which are sequences of repetitive short nucleotides, are abundant in the genome and have relatively many alleles at a locus. Hence, microsatellite markers are used in various research areas such as medicine, agriculture, and biology. Thanks to recent advanced techniques and databases associated with microsatellite marker development, foreign research relying on microsatellite markers is increasing in various study areas. In this study, by analyzing microsatellites-related articles published during 2000-2014 from eight Korean national journals representing zoology, botany, genetics, ecology and environmental science, breeding science, and forest science ('Animal Cells and Systems', 'Journal of Plant Biology', 'Genes and Genomics', 'Korean Society of Environment and Ecology', 'Korean Journal of Breeding Science', 'Journal of Agricultural Science, Chungnam National University', 'Journal of Korean Forest Society' and 'Forest Science and Technology'), we found that the number of articles and diversity of study subjects and objects have increased considerably. However, there are fewer applications of microsatellites in the national forest science area. During 2000-2014 in 'Journal of Korean Forest Society', the percentage of articles dealing with microsatellite markers was found to be the lowest with 4.2% among articles focusing on PCR-based markers including RAPD, AFLP, and ISSR. However, in 'Canadian Journal of Forest Research' and 'Forest Ecology and Management', microsatellite marker articles were represented at their highest with 69.2% and 76.2%, respectively. Given the advantages of microsatellite markers, the publication of research papers using microsatellites should be increased in Korean forest science journals to the level of studies published in prominent international journals.

• Korean Journal of Food Science and Technology
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• v.47 no.1
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• pp.126-131
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• 2015

Pathogenic Escherichia coli is recognized as an important cause of diarrhea, hemorrhagic colitis and hemolytic-uremic syndrome worldwide. This study was conducted to investigate the prevalence E. coli contamination in the Korean traditional food bibimbap. E. coli were isolated from 84 of 1142 (7.3%) bibimbap investigated from 2005 to 2011. Antibiotic resistance profiling demonstrated that 6 of the 84 isolates (7.2%) showed multiple drug resistance. Fifteen virulence genes specific for pathogenic E. coli such as Shiga toxin-producing E. coli (STEC), enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), and enteroaggregative E. coli (EAEC) were examined by multiplex PCR for mixed bacterial cultures derived from bibimbap samples. The EPEC virulence gene (ent) was detected in 5 strains (5.9%), while ETEC, EAEC, and EIEC were not detected. STEC serotypes O103 (1.2%), O91 (1.2%), and O128 (6.0%) were found, but other serogroups such as O26, O157, O145, O111 and O121 were not detecded. Automated Repetitive-Sequence-Based PCR analysis showed different patterns.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.402-406
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• 2007

This study was performed to develop the molecular marker for sex determination of hare (Lepus coreanus) distributed in Korea which focused on sexual dimorphism between X and Y chromosomal homologous genes, zinc finger-X (ZFX) and -Y (ZFY). The intron 7 regions of ZFX and ZFY genes exhibited differential amplification patterns between male and female hares. The lengths of intron 7 region of ZFX and ZFY genes were 538 and 233-bp, respectively. Especially, the ZFX intron 7 contained a repetitive sequence identified as member of RNA-mediated transposable elements which was similar to CSINE2 commonly found in the rabbit genome. However, it was not present in intron 7 of ZFY gene. The molecular sex typing by polymerase chain reaction (PCR) was also carried out to determine the sex of hare based on difference in lengths between the intron 7 regions of ZFX and ZFY genes. All DNA samples tested had common band amplified from ZFX. However, the male hare DNAs had two distinct bands which amplified from ZFX and ZFY genes, respectively. The results from ZFX-ZFY PCR sex typing were identical to those from phenotypic investigation and from amplification patterns using male-specific sex determining region Y (SRY) gene as well. Finally, this study suggested that the sexual dimorphism between intron 7 regions of ZFX and ZFY could be useful genetic marker to determine sex of hare.