• The Korean Journal of Malacology
• /
• v.17 no.1
• /
• pp.1-6
• /
• 2001

The genetic relationship was examined with PCR-RAPD markers among three scallop species, Chlamys farreri farreri, Patinopecten yessoensis, and Agropecten irradians. Six primers were selected from 60 primers used to compare PCR-RAPD profiles among species. All primers showed distinct RAPD band patterns between the three species. In Chiamys farreri farreri, the morphological characteristics such as shell size and color were considerably different between the two geographical populations. RAPD profile, however, showed that no significant genetic differences were found between the two geographical populations. Polymorphic alleles were observed within a population of each species. Thus, PCR-RAPD markers are useful in identifying scallop species and in understanding scallop population genetic structure.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.22 no.2
• /
• pp.427-430
• /
• 2008

Serious controls and cares using ID numbers and barcode needed throughly to have appropriate management in clinical tissues and nucleic acids inventories because these samples are the most essential and important materials in the experimental research laboratories. While almost all of the laboratories using and handling DNA samples as starting materials in their research, problems such as mixing up of two or more different samples together, contamination with other samples, and/or mistakes can occur, especially when it comes with large number of samples. These problems are rather frequent even though researchers pay more attentions to be far away from these obstacles. It has been such a long time since PCR became useful as an important and essential biological research tool among lots of bio-scientific research methods. In this research, we tried to set up a simple and cost-effective genotyping method using PCR and agarose gels, instead of expensive automated machines, for identification and discrimination among those DNA samples, as a kind of low level quality control and sample inventory management.

• Korean Journal of Food Science and Technology
• /
• v.42 no.3
• /
• pp.355-360
• /
• 2010

Vibrio parahaemolyticus (V. parahaemolyticus), which is commonly found in raw seafood, causes gastroenteritis in humans. Rapid and effective methods have been developed as culture methods require up to 5-7 days. In this study, real-time PCR was compared with the standard culture method for detecting V. parahaemolyticus in seafood and radish sprout samples. Five hundred grams of the samples were artificially contaminated with V. parahaemolyticus then divided into 20 samples. The samples were incubated in alkaline peptone water and then streaked onto thiosulfate-citrate-bile saltssucrose agar. Biochemical tests for suspicious colonies were performed using the API 20NE strip. In parallel, real-time PCR was performed targeting the toxR gene using the enrichment broth. The real-time PCR was sensitive in discriminating V. parahaemolyticus from other foodborne pathogens. The detection limit of the real-time PCR was $10^3\;CFU/mL$ in phosphate-buffered saline. Although the real-time PCR detected more positive samples (76 out of 180, 42%) than the culture method (66 out of 180, 37%), there was no significant statistical difference (p>0.05) between the two methods. In conclusion, real-time PCR assays could be an alternative to the standard culture method for detecting V. parahaemolyticus in seafood and radish sprouts, which has many advantages in terms of detection time, labor, and sensitivity.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.48 no.5
• /
• pp.731-738
• /
• 2015

Nematode infection in the epithelial tissue of cultured rockfish Sebastes schlegeli was first reported in 2012. Since then, nematode infections have caused serious economic losses in rockfish aquaculture on the west coast of Korea. Taxonomic and life cycle information for this parasite are currently unknown. In this study, 18S rRNA and cytochrome c oxidase subunit I (COI) genes were used for molecular identification and polymerase chain reaction (PCR) to detect the invisible stages of this parasite. Nucleotide sequences of the 18S rRNA of the rockfish nematode showed 98% identity with that of Philometra morii. Therefore, this rockfish nematode was classified to the Philometridae family. However, we could not identify it to genus level using 18S rRNA. Its COI nucleotide sequences shared 85% and 82% identities with those of Bursaphelenchus sinensis and Philometra overstreeti, respectively. In addition, two gene-specific primer sets were designed based on the 18S rRNA gene to detect the intermediate host and nematode larvae. These primers were specific to this rockfish nematode without cross-reacting to other pathogens. The detection limit of the PCR assay using these primers was 1,000 copies of nematoda plasmid DNA. Therefore, the PCR assay described here is suitable for the detection of nematode DNA within rockfish. In addition, this PCR assay could be used to detect nematode larvae and the intermediate host.

• The Korean Journal of Mycology
• /
• v.40 no.1
• /
• pp.11-18
• /
• 2012

This study was carried out to identify the genetic diversity of Penicillium isolates that were isolated from pears with postharvest decay in storage. URP-PCR was used to detect DNA diversity of 84 Penicillium isolates. Based on URP-PCR profiles, 18 Penicillium isolates were selected and their PCR polymorphic bands were produced by additional primers URP1F, URP2R, URP2F, and URP4R. UPGMA cluster analysis using the polymorphic bands showed four clustered groups and futhermore cultural and morphological features characterized the 18 Penicillium isolates. Group 1 was dominant, which occupies 70% in the four clustered groups and identified as P. expansum based on ITS sequence and morphological features.

• Journal of Food Hygiene and Safety
• /
• v.26 no.2
• /
• pp.114-119
• /
• 2011

In this study, two duplex real-time PCR approach with melting curve analysis is presented for the detection of Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp. and Staphylococcus aureus, which are important food-borne bacterial pathogens usually present in fresh and/or minimally processed vegetables. Reaction conditions were adjusted for the simultaneous amplification and detection of specific fragments in the ${\beta}$-glucuronidase (uidA, E. coli), thermonuclease (nuc, S. aureus), hemolycin (hly, L. monocytogenes) and tetrathionate reductase (ttr, Salmonella spp.) genes. Melting curve analysis using a SYBR Green I real-time PCR approach showed characteristic $T_m$ values demonstrating the specific and efficient amplification of the four pathogens; $80.6{\pm}0.9^{\circ}C$, $86.9{\pm}0.5^{\circ}C$, $80.4{\pm}0.6^{\circ}C$ and $88.1{\pm}0.11^{\circ}C$ for S. aureus, E. coli O157:H7, L. monocytogenes and Salmonella spp., respectively. For all the pathogens, the two duplex, real-time PCR was equally sensitive to uniplex real-time PCR, using same amounts of purified DNA, and allowed detection of 10 genome equivalents. When our established duplex real-time PCR assay was applied to artificially inoculated fresh lettuce, the detection limit was $10^3$ CFU/g for each of these pathogens without enrichment. The results from this study showed that the developed duplex real-time PCR with melting curve analysis is promising as a rapid and cost-effective test method for improving food safety.

• Korean Journal of Animal Reproduction
• /
• v.23 no.2
• /
• pp.159-163
• /
• 1999

Recent development of the molecular biology techniques has made it possible to characterize and analyze early diagnoses of genetic disorders and economic trait loci. In this study, porcine genomic DNA was extracted from both clotted and dried blood to analyze the porcine estrogen receptor (ER) gene by polymerase chain reaction (PCR). By the methods reported here, genomic DNA extracted from clotted or dried blood was efficient enough to detect ER gene by PCR. Moreover, the PCR-RFLP (restriction fragment length polymorphism) of ER gene was identified by PvuII restriction enzyme. Thus the results obtained from this study show that the clotted and dried blood was useful for identification of the certain genotype in a rapid manner with low cost. Importantly, this study implies that the whole blood can be economically utilized in studies of endocrinology, molecular biology, and genetics by obtaining both serum and DNA simultaneously in an efficient manner.

• Research in Plant Disease
• /
• v.19 no.4
• /
• pp.265-272
• /
• 2013

Totally sixty three bacteria were isolated from lower stems showing symptoms of bacterial wilt on pepper plants in 14 counties of 7 provinces, Korea. The isolates showed strong pathogenicity on red pepper (cv. Daewang) and tomato (cv. Seogwang) seedlings. All virulent bacteria were identified as Ralstonia solanacearum based on colony types, physiological and biochemical tests and polymerase chain reaction (PCR). All R. solanacearum isolates from peppers were race 1. The bacterial isolates consisted of biovar 3 (27%) and biovar 4 (73%). Based on polymorphic PCR bands generated by repetitive sequence (rep-PCR), the 63 R. solanacearum isolates were divided into 12 groups at 70% similarity level. These results will be used as basic materials for resistant breeding program and efficient control against bacterial wilt disease of pepper.

• Microbiology and Biotechnology Letters
• /
• v.30 no.2
• /
• pp.116-122
• /
• 2002

The partial 165 rDNA sequences of 6 lactic acid bacterial strains isolated from Kimchi were determined. Two strains were Leuconostoc mesenteroides and the rest were incorrectly classified and turned out to be Lactobacillus. As the case of dairy lactic acid bacteria, the strains isolated from Kimchi also had cell-envelope proteinase (CEP) activity. As the result of partial CEP gene amplification with CEP-specific primers, the expected 1.2-kb amplificate was obtained not from Leu. mesenteroides but from Lactobacillus strains. The deduced amino acid sequence of PCR product amplified from the genomic DNA of Lactobacillus pentosus KFR1821 showed 95％ and 92％ homology with those of PrtPs from Lactococcus lactis subsp. cremoris and Lactobacillus paracasei subsp. paracasei, respectively. The PCR amplificate was used as a probe and the result of Southern hybridization illuminated the location of CEP gene in chromosomal DNA of Lb. pentosus KFR1821.

• Korean Journal of Veterinary Research
• /
• v.55 no.2
• /
• pp.105-110
• /
• 2015

A real-time PCR assay using hybridization probe (HybProbe) has been developed to detect Brucella (B.) melitensis strains. The primer and HybProbe sets were designed based on the gap gene of chromosome I with a specific single nucleotide polymorphism of B. melitensis. Specificity of the assay was confirmed by comparison to reference Brucella species and other related strains. In the melting curve analysis, B. melitensis generated a peak at $67^{\circ}C$ unlike those for other Brucella species observed at $61^{\circ}C$. Sensitivity of the assay for B. melitensis ranged from 20 ng to 200 fg of genomic DNA. The ability to identify 94 Mongolian B. melitensis isolates using the real-time PCR assay was identical to that of classical biotyping methods and differential multiplex PCR. These data showed that this new molecular technique is a simple and quick method for detecting B. melitensis, which will be important for the control and prevention of brucellosis.