• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1398-1403
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• 2016

The simultaneous detection and accurate identification of hepatitis A virus (HAV) is critical in food safety and epidemiological studies to prevent the spread of HAV outbreaks. Towards this goal, a one-step duplex reverse-transcription (RT)-PCR method was developed targeting the VP1/P2B and VP3/VP1 regions of the HAV genome for the qualitative detection of HAV. An HAV RT-qPCR standard curve was produced for the quantification of HAV RNA. The detection limit of the duplex RT-PCR method was 2.8 × 10¹ copies of HAV. The PCR products enabled HAV genotyping analysis through DNA sequencing, which can be applied for epidemiological investigations. The ability of this duplex RT-PCR method to detect HAV was evaluated with HAV-spiked samples of fresh lettuce, frozen strawberries, and oysters. The limit of detection of the one-step duplex RT-PCR for each food model was 9.4 × 10² copies/20 g fresh lettuce, 9.7 × 10³ copies/20 g frozen strawberries, and 4.1 × 10³ copies/1.5 g oysters. Use of a one-step duplex RT-PCR method has advantages such as shorter time, decreased cost, and decreased labor owing to the single amplification reaction instead of four amplifications necessary for nested RT-PCR.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.210-217
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• 2018

A one-step multiplex reverse transcription PCR (RT-PCR) method comprising six primer sets (for the detection of norovirus GI and GII, hepatitis A virus, rotavirus, and astrovirus) was developed to simultaneously detect four kinds of pathogenic viruses. The size of the PCR products for norovirus GI and GII, hepatitis A virus (VP3/VP1 and P2A regions), rotavirus, and astrovirus were 330, 164, 244, 198, 629, and 449 bp, respectively. The RT-PCR with the six primer sets showed specificity for the pathogenic viruses. The detection limit of the developed multiplex RT-PCR, as evaluated using serially diluted viral RNAs, was comparable to that of one-step single RT-PCR. Moreover, this multiplex RT-PCR was evaluated using food samples such as water, oysters, lettuce, and vegetable product. These food samples were artificially spiked with the four kinds of viruses in diverse combinations, and the spiked viruses in all food samples were detected successfully.

• Journal of Life Science
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• v.28 no.5
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• pp.555-562
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• 2018

Swine influenza virus (SIV) causes one of the most common diseases of the pig population, and its subtypes are determined by hemagglutinin (HA) and neuraminidase (NA). Recently, the SIV subtype diagnosis has been developed. The method using antigen-antibody reaction rather than PCR was mainly used because of the large change in the ribonucleotide sequences of SIV. Here, we have developed 10 diagnostic primer sets through multi-nucleotide sequences alignment of spreaded SIV since 2008 in Korea and then optimized the reaction of the one-step RT-PCR for rapid determination of SIV subtype. In addition, specific primers were designed to early determine the pandemic SIV by detecting unique M sequences proven in highly infectious and virulent subtypes of the influenza H1N1 (pH1N1). Here, some of the SIVs spread in Korea from 2008 to 2014 have been tested to determine the subtypes and pandemic potential of SIV. All diagnostic primer sets were found to be able to accurately determine the SIV subtype and to detect the pandemic SIV. In conclusion, it was confirmed that the optimized one-step RT-PCR analysis using these primer sets is useful for rapid diagnosis of SIV subtypes. These results can be used for development of SIV subtype diagnostic kit to early detect before virulent SIV spreads do.

• Journal of Microbiology
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• v.38 no.4
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• pp.260-264
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• 2000

Reverse transcription (RT)-PCR and nested PCR methods (2-step PCR) were tested for their ability to detect marine birnavirus (MBV) in cultured rockfish, Sebastes schlegeli. One set of primers for RT-PCR was designed, based on a gene of infectious pancreatic necrosis virus (IPNV), and another set of primers for nested PCR was designed based on the VP2/NS junction region of MBV. This 2-step PCR method was specific for MBV and sensitivity was heightened when nested PCR was combined to RT-PCR. This 2-step PCR method was useful for detecting MBV not only in diseased fish, but also in asymptomatic fish. These results indicate that this 2-step PCR method is useful for detecting MBV in rockfish.

• Korean Journal of Veterinary Service
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• v.37 no.4
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• pp.263-271
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• 2014

In this study, we developed a cost and time saving one-step multiplex RT-PCR for the simultaneous detection and differentiation of swine influenza viruses (SIV) and 2009 pandemic influenza H1N1 virus (pH1N1). The one-step multiplex RT-PCR using four sets of primer was confirmed to be capable of detection of all SIV subtypes and differential diagnosis of major SIV subtype H1, H3 and pH1N1 on individual or mixed viral culture samples. The sensitivity of the multiplex RT-PCR was determined to be at least $2^{-6}$ $HA/25{\mu}L$ of the presented SIVs, providing sufficient efficacy for a routine SIV monitoring in diagnostic laboratories. In addition, compared with the conventional RT-PCR methods that cannot avoid the carryover DNA contamination, the developed RT-PCR applied with the uracil DNA glycosylase (UNG) system was proven to prevent a false positive reaction by carryover contamination of the pre-amplified DNA. In conclusion, the one-step RT-PCR with UNG system could be applicable to detect and differentiate of SIV from the viral cultures without worry of carryover DNA contamination in clinical laboratories.

• Research in Plant Disease
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• v.7 no.2
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• pp.80-85
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• 2001

This study was carried out to examine tne incidences of virus diseases in lily plants cultivated in highland areas, and to develop an effective detection method. Viral symptoms on lilies in the highland areas were differentiated into mosaic, crinkle, mottle, stripe and line pattern. The distribution of symptoms on infected plants was 43.8% of mosaic, 29.2% of crinkle, and 10.9% of mottle symptoms. Six viruses such as Lily symptomless vires(LSV), Cucumber mosaic virus (CMV), Lily mottle virus (LMoV), Lily virus X (LVX, Potexvirus), Tabacco mosaic virus (TMV,Tobamovirus), and Tabacco rattle virus (TRV,Tobravirus) were detected from the infected lilies. Infection rate of Lilium oriental (cvs. Casablanca and Marcopolo) was 2~4 times higher than that of L. asiatic (cvs. Solemio and Prato). Virus detection on lilies by one-step RT-PCR (by using reverse transcription and polymerase chain reaction simultaneously) was more rapid rapid and reliable than by the conventional RT-PCR method.

• Journal of Plant Biotechnology
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• v.49 no.3
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• pp.193-206
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• 2022

Astringent persimmon (Diospyros kaki Thunb.) is an important fruit crop in Korea; it possesses significant medicinal potential. However, knowledge regarding the pathogens affecting this crop, particularly, viruses and viroids, is limited. In the present study, reverse transcription-polymerase chain reaction (RT-PCR) and high-throughput transcriptome sequencing (HTS) were used to investigate the viruses and viroids infecting astringent persimmons cultivated in Korea. A one-step multiplex RT-PCR (mRT-PCR) method for the simultaneous detection of the pathogens was developed by designing species-specific primers and selecting the primer pairs via combination and detection limit testing. Seven of the sixteen cultivars tested were found to be infection-free. The RT-PCR and HTS analyses identified two viruses and one viroid in the infected samples (n = 51/100 samples collected from 16 cultivars). The incidence of single infections (n = 39/51) was higher than that of mixed infections (n = 12/51); the infection rate of the Persimmon cryptic virus was the highest (n = 31/39). Comparison of the monoplex and mRT-PCR results using randomly selected samples confirmed the efficiency of mRT-PCR for the identification of pathogens. Collectively, the present study provides useful resources for developing disease-free seedlings; further, the developed mRT-PCR method can be extended to investigate pathogens in other woody plants.

• Horticultural Science & Technology
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• v.18 no.4
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• pp.513-517
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• 2000

This experiment was carried out to detect the cymbidium mosaic virus (CymMV) and the odontoglossum ringspot virus (ORSV) in the seed-derived plantlets of Phalaenopsis imported from Taiwan by one-step reverse transcription-polymerase chain reaction (RT-PCR). Simple and rapid crude plant extracts for RT-PCR were prepared. The reverse transcription step was performed at $42^{\circ}C$ for 45 min and the following thermal cycling scheme was used for 36 reaction cycles: template predenaturation at $96^{\circ}C$ for 2 min, template denaturation at $96^{\circ}C$ for 30 s, primer annealing at $60^{\circ}C$ for 30 s, and DNA synthesis at $72^{\circ}C$ for 1 min. Of the 40 seed-derived plantlets of Phalaenopsis imported from Taiwan, all of them were infected with CymMV, but ORSV was not detected.

• Journal of Life Science
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• v.18 no.3
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• pp.374-380
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• 2008

Rapid detection of enterovirus (EVs) is important in the management of aseptic meningitis. We examined the relative efficiency and specificity of the real-time nucleic acid sequence-based amplification (NASBA) comparing with the established reverse transcription polymerase chain reaction (RT-PCR) and viral culture method which were used for the detection of enterovirus RNA in clinical specimens. Of the total 292 samples, 145 were found to be positive to enterovirus RNA by real-time NASBA, 101 were positive by viral culture, and 86 were positive by RT-PCR. 147 samples and 46 samples were determined to be negative and positive by all methods respectively, but 4 samples were positive only by real-time NASBA. To compare the specificity of each method, various clinical samples which were diagnosed for herpes simplex virus (HSV)-1, HSV-2, adenovirus, mumps, and rhinovirus were applied. Except one rhinovirus sample which was false positive to enterovirus RNA by RT-PCR, the other different samples were negative to all three methods. The real-time NASBA procedure can be completed within 5 hours in contrast with 9 hours for the RT-PCR and 3-14 days for the viral culture. From this study, it was suggested that the real-time NASBA assay could be a standardized, rapid, specific, and sensitive procedure for the detection of enterovirus RNA.

• Research in Plant Disease
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• v.17 no.1
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• pp.52-58
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• 2011

The aim of this research was to develop specific and sensitive PCR-based procedures for simultaneous detection of economically important plant pathogenic bacteria and seed borne virus in commercial Brassicaceae crop seeds, Xanthomonns campestris pv. campestris (Xcc) and Lettuce Mosaic Virus (LMV). Bacterial and virus diseases of Brassicaceae leaves are responsible for heavy losses. PCR with arbitral primers: selection of specific primers, performance of PCR with specific primers and determination of the threshold level for pathogens detection. To detect simultaneously the Xcc and LMV in commercial Brassicaceae crop seeds (lettuce, kohlrabi, radish, chinese cabbage and cabbage), two pairs of specific primer (LMV-F/R, Xcc-F/R) were synthesized by using primer-blast program (http://www.ncbi.nlm.nih.gov/tools/primer-blast/). The multiplex PCR for the two pathogens in Brassicaceae crop seeds could detect specifically without interference among primers and/or cDNA of other plant pathogens. The pathogen detection limit was determined at 1 ng of RNA extracted from pathogens. In the total PCR results for pathogen detection using commercial kohlrabi (10 varieties), lettuce (50 varieties), radish (20 varieties), chinese cabbage (20 varieties) and cabbage (20 varieties), LMV and Xcc were detected from 39 and 2 varieties, respectively. In the PCR result of lettuce, LMV and Xcc were simultaneously detected in 8 varieties.