• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.318-324
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• 2006

In order to develop an oral vaccine to prevent H. pylori infection, we have expressed the hpaA gene of H. pylori K51 isolated from Korean patients, encoding 29-kDa HpaA that is known to be localized on the cell surface and flagella sheath, in a live delivery vector system, Lactococcus lactis. The hpaA gene, amplified by PCR using the genomic DNA of H. pylori K51, was cloned in the pGEX-2T vector, and the DNA sequence analysis revealed that the hpaA gene of H. pylori K51 had 99.7% and 94.8% identity with individual hpaA genes of the H. pylori 26695 strain (U.K) and the J99 strain (U.S.A). A polyclonal anti-HpaA antibody was raised in rats using GST-HpaA fusion protein as the antigen. The hpaA gene was inserted in an E. coli-L. lactis-shuttle vector (pMG36e) to express in L. lactis. Western blot analysis showed that the expression level of HpaA in the L. lactis transformant remained constant from the exponential phase to the stationary phase, without extracelluar secretion. These results indicate that the HpaA of H. pylori K51 was successfully expressed in L. lactis, and suggest that the recombinant L. lactis expressing HpaA may be applicable as an oral vaccine to induce a protective immune response against H. pylori.

• The Plant Pathology Journal
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• v.30 no.2
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• pp.200-207
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• 2014

A viral disease causing severe mosaic, necrotic, and yellow symptoms on Vigna angularis var. nipponensis was prevalent around Suwon area in Korea. The causal virus was characterized as Cucumber mosaic virus (CMV) on the basis of biological and nucleotide sequence properties of RNAs 1, 2 and 3 and named as CMV-wVa. CMV-wVa isolate caused mosaic symptoms on indicator plants, Nicotiana tabacum cv. Xanthi-nc, Petunia hybrida, and Cucumis sativus. Strikingly, CMV-wVa induced severe mosaic and malformation on Cucurbita pepo, and Solanum lycopersicum. Moreover, it caused necrotic or mosaic symptoms on V. angularis and V. radiate of Fabaceae. Symptoms of necrotic local or pin point were observed on inoculated leaves of V. unguiculata, Vicia fava, Pisum sativum and Phaseolus vulgaris. However, CMV-wVa isolate failed to infect in Glycine max cvs. 'Sorok', 'Sodam' and 'Somyeong'. To assess genetic variation between CMV-wVa and the other known CMV isolates, phylogenetic analysis using 16 complete nucleotide sequences of CMV RNA1, RNA2, and RNA3 including CMV-wVa was performed. CMV-wVa was more closely related to CMV isolates belonging to CMV subgroup I showing about 85.1-100% nucleotide sequences identity to those of subgroup I isolates. This is the first report of CMV as the causal virus infecting wild Vigna angularis var. nipponensis in Korea.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.251-259
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• 2007

Two isolates of Cucumber mosaic virus (CMV) originated from lily plants, named Ly2-CMV and Ly8-CMV, were compared with their pathological features in several host plants. Ly2-CMV and Ly8-CMV could induce systemic mosaic symptom in Nicotiana benthamiana, but Ly2-CMV could not systemically infect tomato and cucumber plants that have been used for CMV-propagative hosts. While Fny-CMV used as a control infected systemically the same host plants, producing typical CMV symptoms. Ly8-CMV could infect systemically two species of tobacco (N. tabacum cv. Xanthi-nc and N. glutinosa) and zucchini squash (Curcubita pepo), but Ly2 failed systemic infection on these plants. As resulted from tissue-print immunoblot assay, different kinetics of systemic movement between Ly2-CMV and Ly8-CMV were crucial for systemic infection in tobacco (cv. Xanthi-nc). Sequence analysis of full-length genome of two lily isolates showed Ly2 and Ly8 belonged to subgroup IA of CMV. The lily isolates shared overall 98 % sequence identity in their genomes. Coat protein, 3a protein, and 2b protein involved in virus movement was highly conserved in genomes of the isolates Ly2 and Ly8. Although there is the low frequency of recombinants and reassortants in natural CMV population, phylogenetic analysis of each viral protein among a number of CMV isolates suggested that genetic variation in a defined population of CMV lily isolates was stochastically produced.

• The Plant Pathology Journal
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• v.29 no.3
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• pp.260-273
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• 2013

The incidence and distribution of Tobacco mosaic virus (TMV) and related tobamoviruses was determined using an enzyme-linked immunosorbent assay on 1,926 symptomatic horticultural crops and 107 asymptomatic weed samples collected from 78 highly infected fields in the major horticultural crop-producing areas in 17 provinces throughout Iran. The results were confirmed by host range studies and reverse transcription-polymerase chain reaction. The overall incidence of infection by these viruses in symptomatic plants was 11.3%. The coat protein (CP) gene sequences of a number of isolates were determined and disclosed to be a high identity (up to 100%) among the Iranian isolates. Phylogenetic analysis of all known TMV CP genes showed three clades on the basis of nucleotide sequences with all Iranian isolates distinctly clustered in clade II. Analysis using the complete CP amino acid sequence showed one clade with two subgroups, IA and IB, with Iranian isolates in both subgroups. The nucleotide diversity within each subgroup was very low, but higher between the two clades. No correlation was found between genetic distance and geographical origin or host species of isolation. Statistical analyses suggested a negative selection and demonstrated the occurrence of gene flow from the isolates in other clades to the Iranian population.

• Parasites, Hosts and Diseases
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• v.56 no.3
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• pp.295-300
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• 2018

Human sparganosis was diagnosed by morphological and genetic analyses in Korea. The complete mitochondrial genomes of Spirometra erinaceieuropaei and S. decipiens isolated in Korea have been recorded. Present study was performed to provide information to diagnose the etiologic agent of sparganosis by multiplex PCR using mitochondrial genome sequences of S. erinaceieuropaei and S. decipiens. In an effort to examine the differential diagnosis of spirometrid tapeworms, multiplex PCR assays were performed on plerocercoid larvae of S. erinaceieuropaei and S. decipiens. The PCR products obtained using species-specific primers were positively detected in all PCR assays on mixture of S. erinaceieuropaei and S. decipiens DNA. S. erinaceieuropaei-specific bands (239 bp and 401 bp) were obtained from all PCR assays using a mixture of S. erinaceieuropaei-specific primers (Se/Sd-1800F and Se-2018R; Se/Sd-7955F and Se-8356R) and S. erinaceieuropaei template DNA. S. decipiens-specific bands (540 bp and 644 bp) were also detected in all PCR assays containing mixtures of S. decipiens-specific primers (Se/Sd-1800F and Sd-2317R; Se/Sd-7955F and Sd-8567R) and S. decipiens template DNA. Sequence analyses on these species-specific bands revealed 100% sequence identity with homologous regions of the mtDNA sequences of S. erinaceieuropaei and S. decipiens. The multiplex PCR assay was useful for differential diagnosis of human sparganosis by detecting different sizes in species-specific bands.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.763-768
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• 2014

The identity of 45 Hanwo and 47 imported beef (non-Hanwoo) samples from USA and Australia were verified using the microsatellite (MS) marker and single nucleotide polymorphism (SNP) methods. Samples were collected from 19 supermarkets located in the city of Seoul and Gyeonggi province, South Korea, from 2009 to 2011. As a result, we obtained a 100% concordance rate between the MS and SNP methods for identifying Hanwoo and non-Hanwoo beef. The MS method presented a 95% higher individual discriminating value for Hanwoo (97.8%) than for non-Hanwoo (61.7%) beef. For further comparison of the MS and SNP methods, blood samples were collected and tested from 54 Hanwoo ${\times}$ Holstein crossbred cattle (first, second, and third generations). By using the SNP and MS methods, we correctly identified all of the first-generation crossbred cattle as non-Hanwoo; in addition, among the second and third generation crossbreds, the ratio identified as Hanwoo was 20% and 10%, respectively. The MS method used in our study provides more information, but requires sophisticated techniques during each experimental process. By contrast, the SNP method is simple and has a lower error rate. Our results suggest that the MS and SNP methods are useful for discriminating Hanwoo from non-Hanwoo breeds.

• Restorative Dentistry and Endodontics
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• v.24 no.4
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• pp.535-545
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• 1999

Crease of Streptococcus salivarius is believed to play a critical role in bacterial ecology and pH homeostasis in the mouth, and consequently affect the pathogenesis of dental caries and periodontal diseases. Expression of the urease gene is greatly enhanced by low p. f. excess of Carbohydrate, and faster growth. It was observed that urease activity of the strains of S. salivarius that exhibited no of low urease activity was not increased even in low pH condition. In this study, it was hypothesized that the urease gene of the strains is absent, defected, or greatly changed by genetic combination. In order to prove this hypothesis, chromosomes were obtained from 28 S. salivarius strains which had been isolated from normal teeth and carious lesions, subjected to polymerase chain reaction (PCR) using primers encoding highly conserved sequence from ureC, and then the obtained PCR products were compared. The results were as follows: 1. After PCR the strains generated either one of 0.54- and 1.3-kbp PCR products, or none. 2. All 16 strains having a higher urease activity(<50${\mu}mol/min/mg$) produced 0.54-kbp PCR products. 3. Twelve strains without urease activity and with a lower urease activity(<50${\mu}mol/min/mg$) yield either one of 0.54 and 1.3-kbp PCR products, or none. 4. The DNA sequence of the 0.54-kbp PCR product (pCAP-0.54) exhibited 95% identity to the ureC of S. salivarus 57.I; 30bp were found to be different, which led to difference of only 2 amino acids in the sequence. 5. The DNA sequence of the 1.3-kbp PCR product(pCAP-1.3) was found to be highly homologous to the aminopeptidase C gene of Streptococcus thermophilus. Overall results indicate that there are considerable variations of the urease genes from S. salivarus strains and the variations may affect the uncolytic activity of the bacteria directly of indirectly.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1235-1244
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• 2008

Indole-3-acetic acid (IAA) is produced commonly by plants and many bacteria, however, little is known about the genetic basis involving the key enzymes of IAA biosynthetic pathways from Bacillus spp. IAA intermediates from the Gram-positive spore-forming bacterium Paenibacillus polymyxa E681 were investigated, which showed the existence of only an indole-3-pyruvic acid (IPA) pathway for IAA biosynthesis from the bacterium. Four open reading frames (ORFs) encoding indole-3-pyruvate decarboxylase-like proteins and putative indole-3-pyruvate decarboxylase (IPDC), a key enzyme in the IPA synthetic pathway, were found on the genome sequence database of P. polymyxa and cloned in Escherichia coli DH5$\alpha$. One of the ORFs, PP2_01257, was assigned as probable indole-3-pyruvate decarboxylase. The ORF consisted of 1,743 nucleotides encoding 581 amino acids with a deduced molecular mass of 63,380 Da. Alignment studies of the deduced amino acid sequence of the ORF with known IPDC sequences revealed conservation of several amino acids in PP2_01257, essential for substrate and cofactor binding. Recombinant protein, gene product of the ORF PP2_01257 from P. polymyxa E681, was expressed in E. coli BL21 (DE3) as a glutathione S-transferase (GST)-fusion protein and purified to homogeneity using affinity chromatography. The molecular mass of the purified enzyme showed about 63 kDa, corresponding closely to the expected molecular mass of IPDC. The indole-3-pyruvate decarboxylase activity of the recombinant protein, detected by HPLC, using IPA substrate in the enzyme reaction confirmed the identity and functionality of the enzyme IPDC from the E681 strain.

• The Korean Society of Law and Medicine
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• v.10 no.1
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• pp.11-38
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• 2009

"Bioethics" may have various meanings depending on its roles. It may mean professional ethics for scientists and physicians, etc. It may also mean an academic discipline using interdisciplinary approach as well as a philosophical or a legal approach. "Bioethics" as an interdisciplinary study should often deal with public policy on bioethical issues. I call this role bioethics as a study of bioethics policy, which has to be developed as a new discipline. From this perspective, I deal with bioethical issues relevant to a human life before birth. There are various and often conflicting arguments about the moral status of a human life before birth such as the fertilization argument, the argument of genetic identity, so-called the "14 days" argument focusing on the formation of primitive streak, the argument of sentient being, and Michael Sandle's argument of an embryo as a being between a thing and a person. I argue that each of them is reasonable. Thus we are faced with reasonable disagreement on the views over whether a human life before birth has the same right to life as that of a person or whether right to life may be considered to be a matter of degree. If we acknowledge reasonable disagreement, as John Rawls pointed out, we should tolerate the views from ours in a plural society. Therefore, we cannot help making a policy that allows abortion and embryonic research with some limitations. When we say a certain act is morally permissible, "moral permissibility" does not mean that the act is morally right for all. Rather it means that the act cannot help being morally allowed for some persons although the others do not believe its moral rightness because they cannot right now rationally persuade others to accept their view.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.751-758
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• 2021

The recessive white (locus c) phenotype observed in chickens is associated with three alleles (recessive white c, albino c^a, and red-eyed white c^re) and causative mutations in the tyrosinase (TYR) gene. The recessive white mutation (c) inhibits the transcription of TYR exon 5 due to a retroviral sequence insertion in intron 4. In this study, we genotyped and sequenced the insertion in TYR intron 4 to identify the mutation causing the unusual white plumage of Yeonsan Ogye chickens, which normally have black plumage. The white chickens had a homozygous recessive white genotype that matched the sequence of the recessive white type, and the inserted sequence exhibited 98% identity with the avian leukosis virus ev-1 sequence. In comparison, brindle and normal chickens had the homozygous color genotype, and their sequences were the same as the wild-type sequence, indicating that this phenotype is derived from other mutation(s). In conclusion, white chickens have a recessive white mutation allele. Since the size of the sample used in this study was limited, further research through securing additional samples to perform validation studies is necessary. Therefore, after validation studies, a selection system for conserving the phenotypic characteristics and genetic diversity of the population could be established if additional studies to elucidate specific phenotype-related genes in Yeonsan Ogye are performed.