• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.246-250
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• 2013

In this study, a loop-mediated isothermal amplification (LAMP) method to rapidly detect Staphylococcus aureus strains was developed and evaluated by extensively applying a large number of S. aureus isolates from clinical and food samples. Six primers were specially designed for recognizing eight distinct sequences on the species-specific femA gene of S. aureus. The detection limits were 100 fg DNA/tube and $10^4$ CFU/ml. The LAMP assay was applied to 432 S. aureus strains isolated from 118 clinical and 314 food samples. Total detection rates for the LAMP and polymerase chain reaction assays were 98.4% (306/311) and 89.4% (278/311), respectively.

• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.335-341
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• 2017

The complexity of the bacterial recombination system is a barrier for the construction of bacterial mutants for the further functional investigation of specific genes. Several protocols have been developed to inactivate genes from the genus Pseudomonas. Those protocols are complicated and time-consuming and mostly do not enable easy construction of multiple knock-ins/outs. The current study describes a single and double crossover-recombination system using an optimized vector-free allele-exchange protocol for gene disruption and gene replacement in a single species of the family Pseudomonadaceae. The protocol is based on self-ligation (circularization) for the DNA cassette which has been obtained by overlapping polymerase chain reaction (Fusion-PCR), and carries an antibiotic resistance cassette flanked by homologous internal regions of the target locus. To establish the reproducibility of the approach, three different chromosomal genes (ncRNA31, rpoN, rpoS) were knocked-out from the root-associative bacterium Pseudomonas stutzeri A1501. The results showed that the P. stutzeri A1501 mutants, which are free of any plasmid backbone, could be obtained via a single or double crossover recombination. In order to optimize this protocol, three key factors that were found to have great effect on the efficiency of the homologous recombination were further investigated. Moreover, the modified protocol does not require further cloning steps, and it enables the construction of multiple gene knock-in/out mutants sequentially. This work provides a simple and rapid mutagenesis strategy for genome editing in P. stutzeri, which may also be applicable for other gram-negative bacteria.

• International Journal of Industrial Entomology and Biomaterials
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• v.29 no.2
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• pp.169-178
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• 2014

In this study, we investigated genetic diversity of 22 microsporidian isolates infecting tropical tasar silkworm, Antheraea mylitta collected from various geographical forest locations in the state of Jharkhand, India, using polymerase chain reaction (PCR)-based marker assay: random amplified polymorphic DNA (RAPD). A type species, NIK-1s_mys was used as control for comparison. The shape of mature microsporidians was found to be oval to elongate, measuring 3.80 to $5.10{\mu}m$ in length and 2.56 to $3.30{\mu}m$ in width. Of the 20 RAPD primers screened, 16 primers generated reproducible profiles with 298 polymorphic fragments displaying high degree of polymorphism (97%). A total of 14 RAPD primers produced 45 unique putative genetic markers, which were used to differentiate the microsporidians. Calculation of genetic distance coefficients based on dice coefficient method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was conducted to unravel the genetic diversity of microsporidians infecting tasar silkworm. The similarity coefficients varied from 0.059 to 0.980. UPGMA analysis generated a dendrogram with four microsporidian groups, which appear to be different from each other as well as from NIK-1s_mys. Two-dimensional distribution based on Euclidean distance matrix also revealed considerable variability among different microsporidians identified from the tasar silkworms. Clustering of few microsporidian isolates was in accordance with the geographic origin. The results indicate that the RAPD profiles and specific/unique genetic markers can be used for differentiating as well as to identify different microsporidians with considerable accuracy.

• Journal of Embryo Transfer
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• v.28 no.4
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• pp.343-348
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• 2013

Cell-free fetal RNA has been highlighted as useful tools for the fetal sex determination or other genetic inherent disorder. However, there is no knowledge about the sex determination using cell free fetal RNA in bovine field. Thus, the present study aimed to evaluate the presence of transcripts of DDX3Y, USP9Y and ZRSR2Y genes in maternal plasma of pregnant cows to determine the sex of the fetus using real-time quantitative polymerase chain reaction assay, and verify its accuracy, sensitivity and specificity compared with the molecular testing and the calf sex at birth. Transcripts of USP9Y and DDX3Y genes were expressed in the all plasma of males and females both the control group and the experimental group. However, ZRSR2Y gene was matched up with the molecular testing and the true sex in control group and has an overall accuracy of 82.6%, a sensitivity of 75%, and a specificity of 100% in experimental group. Therefore, these results indicated that real time PCR technique, as a noninvasive and cost-efficient method, is possible to determination fetal sex in the bovine species using circulating cell free RNA in maternal plasma and especially ZRSR2Y gene could be a good candidate for the RNA based sex determination work.

• Parasites, Hosts and Diseases
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• v.57 no.3
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• pp.233-242
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• 2019

Detailed description of malaria in low transmission areas is crucial for elimination. The current study aimed to provide a comprehensive description for malaria transmission in Jazan, a low transmission district, southwestern Saudi Arabia. Patients at a tertiary care hospital were recruited in our study between August 2016 and September 2018. Malaria diagnosis was performed through a species-specific nested polymerase chain reaction (nested PCR), microscopy and Paramax-$3^{TM}$ rapid detection test (RDT). Malaria was detected in 30 patients by the PCR, with point prevalence of 10.9%. Of these malaria infections, 80% was imported, 26.6% was asymptomatic and 23.3% was sub-microscopic. Malaria was reported throughout the year, with February/March and September/October peaks. Infection was significantly more in males than in females (P=0.01). Likewise, infections were detected more in febrile than in non-febrile patients (P=0.01). Adult aged 15-24 years, fever and travel were identified as high-risk factors. Malaria was primarily attributed to Plasmodium falciparum mono-infections, followed by P. vivax mono-infections and lastly to falciparum/vivax mixed infections accounting 76.6%, 16.6%, and 6.6% of PCR-confirmed malaria cases, respectively. The nested PCR was superior to the smear microscopy (sensitivity 76.6%; specificity 100%) and the RDT (sensitivity 83.3%, specificity 94.2%). The overall percent agreement between microscopy and the RDT was 92.7% (kappa=0.63). High proportion of imported malaria including sub-microscopic and sub-patent cases were described. We suggest that incorporation of molecular tool into the conventional malaria diagnosis is beneficial in Jazan district.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.141.2-142
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• 2003

A flexuous rod-shaped virus was isolated from Cucurbita pepo leaves showing green mosaic and puckering symptoms at Anseong, Korea. Based on the biological tests, electron microscopy, and reverse transcription-polymerase chain reaction (RT-PCR), the isolate was identified as Papaya ringspot virus type Watermelon (PRSV-W). In the biological test, host range of PRSV-W was limited in the families Cucurbitaceae and Chenopodiaceae. Most susceptible cucurbit species, such as Cucurmis lanatus, Cucurmis sativus, Cucurbita pepo, and Citrullus lanatus, responded to mechanical inoculation by PRSV-W that induce green mosaic, malformation, puckering, and narrow laminae. The local lesion symptoms were produced on the inoculated leaves of Chenopodium maranticolor and C. quinoa PRSV specific primers which amplifies the part of the coat protein (CP) genes, generated a 648 bp product from 6 isolates of PRSV-W, but no amplification had been detected in other viruses including CMV, CGMMV, KGMMV, ZYMV and WMV. In electron microscopy, PRSV particles were flexuous, approximately 780 nm in length and 12 nm in width. PRSV-W is one of the worldwide viruses which has the great economic importance in cucumber, melon, squash, watermelon, and other cultivated cucurbits with ZYMV and WMV. This is the first report of PRSV-W on cucurbits in Korea.

• Journal of Veterinary Science
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• v.24 no.4
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• pp.53.1-53.12
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• 2023

Background: Mammalian orthoreovirus type 3 (MRV3), which is responsible for gastroenteritis in many mammalian species including pigs, has been isolated from piglets with severe diarrhea. However, the use of pig-derived cells as an infection model for swine-MRV3 has rarely been studied. Objectives: This study aims to establish porcine intestinal organoids (PIOs) and examine their susceptibility as an in vitro model for intestinal MRV3 infection. Methods: PIOs were isolated and established from the jejunum of a miniature pig. Established PIOs were characterized using polymerase chain reaction (PCR) and immunofluorescence assays (IFAs) to confirm the expression of small intestine-specific genes and proteins, such as Lgr5, LYZI, Mucin-2, ChgA, and Villin. The monolayered PIOs and three-dimensional (3D) PIOs, obtained through their distribution to expose the apical surface, were infected with MRV3 for 2 h, washed with Dulbecco's phosphate-buffered saline, and observed. Viral infection was confirmed using PCR and IFA. We performed quantitative real-time reverse transcription-PCR to assess changes in viral copy numbers and gene expressions linked to intestinal epithelial genes and antiviral activity. Results: The established PIOs have molecular characteristics of intestinal organoids. Infected PIOs showed delayed proliferation with disruption of structures. In addition, infection with MRV3 altered the gene expression linked to intestinal epithelial cells and antiviral activity, and these effects were observed in both 2D and 3D models. Furthermore, viral copy numbers in the supernatant of both models increased in a time-dependent manner. Conclusions: We suggest that PIOs can be an in vitro model to study the infection mechanism of MRV3 in detail, facilitating pharmaceutical development.

• Animal Bioscience
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• v.36 no.12
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• pp.1905-1917
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• 2023

Objective: Nanog homeobox (NANOG) is a core transcription factor that contributes to pluripotency along with octamer binding transcription factor-4 (OCT4) and sex determining region-Y box-2 (SOX2). It is an epiblast lineage marker in mammalian pre-implantation embryos and exhibits a species-specific expression pattern. Therefore, it is important to understand the lineage of NANOG, the trophectoderm, and the primitive endoderm in the pig embryo. Methods: A loss- and gain-of-function analysis was done to determine the role of NANOG in lineage specification in parthenogenetic porcine blastocysts. We analyzed the relationship between NANOG and pluripotent core transcription factors and other lineage makers. Results: In NANOG-null late blastocysts, OCT4-, SOX2-, and SOX17-positive cells were decreased, whereas GATA binding protein 6 (GATA6)-positive cells were increased. Quantitative real-time polymerase chain reaction revealed that the expression of SOX2 was decreased in NANOG-null blastocysts, whereas that of primitive endoderm makers, except SOX17, was increased. In NANOG-overexpressing blastocysts, caudal type homeobox 2 (CDX2-), SOX17-, and GATA6-positive cells were decreased. The results indicated that the expression of primitive endoderm markers and trophectoderm-related genes was decreased. Conclusion: Taken together, the results demonstrate that NANOG is involved in the epiblast and primitive endoderm differentiation and is essential for maintaining pluripotency within the epiblast.

• The Plant Pathology Journal
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• v.40 no.4
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• pp.390-398
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• 2024

The Chinese artichoke (Stachys affinis syn. S. sieboldii) is a widely cultivated crop, and its rhizome is used as a medicinal vegetable. To investigate the causes of viral diseases in Chinese artichokes, the infection rates of four virus species infecting Chinese artichoke were investigated. Since the Chinese artichoke propagates through its tuber, this study aimed to determine whether viral transmission to the progeny is possible through the tuber, by identifying the virus present in the tuber and investigating its accumulation. First, reverse transcription polymerase chain reaction analysis was performed to detect viruses using total RNA extracted from the flowers, leaves, and tubers of Chinese artichoke plants. Alfalfa mosaic virus (AMV) and Chinese artichoke mosaic virus (ChAMV) had high infectivity in Chinese artichoke and most plants were simultaneously infected with AMV and ChAMV. These viruses were present in all tissues, but their detection frequency and accumulation rates varied across different tissues of the Chinese artichoke. Also, we sequenced the coat protein (CP) genes of AMV and ChAMV to investigate genetic variations of virus between the leaf and tuber. It provides information on CP gene sequences and genetic diversity of isolates identified from new hosts of AMV and ChAMV. This study offers valuable insights into the distribution and spread of the ChAMV and AMV within Chinese artichoke plants, which have implications for the management and control of viral infections in crops.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.637-650
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• 2006

Genomic DNA isolated from two crucian carp species obtained from Yesan (Carassius auratus) and Dangjin (Carassius cuvieri) in Korea were amplified at several times by polymerase chain reaction (PCR). The amplified products were separated by agarose gel electrophoresis (AGE) with oligonucleotides decamer primer and stained with ethidium bromide. The seven arbitrarily selected primers OPC-11, OPC-14, OPC-18, OPD- 02, OPD-11, OPD-15 and OPD-20 generated the shared loci by each species, the polymorphic and specific loci. The seven primers generated the total 458 loci that can be scored from the crucian carp obtained in C. auratus species. 358 fragments were generated from the species obtained in C. cuvieri species. The size of DNA fragments varies from 150 to 1,600bp. The complexity of the banding patterns varies dramatically between the primers and two locations. In this study, 458 loci were identified in the crucian carp species from Yesan and 358 in the crucian carp species from Dangjin: 84 polymorphic loci (18.3%) in the C. auratus species and 48 (13.4%) in the C. cuvieri species. 154 shared loci by each species, the average 22 per primer, were observed in the C. auratus species and 187 loci, the average 26.7 per primer, in the Dangjin species. Based on the average bandsharing (BS) values of all samples, the similarity matrix ranged from 0.434 to 0.868 in the C. auratus species and from 0.449 to 0.924 in the C. cuvieri species. The average BS value was 0.641±0.013 within the C. auratus species and 0.684±0.013 within the C. cuvieri species. The average BS value between two crucian carp species 0.484 ± 0.007, ranged from 0.307 to 0.682. The BS value between the individual No. 09 and No. 16 was 0.682, which was the highest between two crucian carp species. Compared separately, the BS value of individuals within the C. cuvieri species was higher than the C. auratus species. The dendrogram obtained by the seven primers, indicates three genetic clusters: cluster 1 (AURATUS No. 01, 02, 03, 04, 05, 06, 07, 08, 09, 10 and 11), cluster 2 (CUVIERI No. 12, 13, 14, 15, 16, 17, 18, 19, 20 and 21) and cluster 3 (CUVIERI no. 22). The shortest genetic distance displaying significant molecular difference was between the individual AURATUS No. 09 and AURATUS No. 08 from Yesan (genetic distance=0.064). The longest genetic distance displaying significant molecular differences was between the individual CUVIERI No. 17 and AURATUS No. 11 between two crucian carp species (0.477). RAPD-PCR analysis has revealed the significant genetic distance between two crucian carp species pairs.(Key words: Carassius auratus, Carassius cuvieri, Crucian Carp, DNA Polymorphism, Genetic Distance)