• Research in Plant Disease
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• v.19 no.4
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• pp.254-258
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• 2013

Fusaric acid (FA) is a mycotoxin produced by Fusarium species. Its toxicity is relatively low but often associated with other mycotoxins, thus enhancing total toxicity. To date, biosynthetic genes or enzymes for FA have not been identified in F. oxysporum. In order to explore the genetic element(s) for FA biosynthesis, restriction enzyme mediated integration (REMI) procedure as an insertional mutagenesis was employed using FA producing-F. oxysporum strains. Genetic transformation of two F. oxysporum strains by REMI yielded more than 7,100 transformants with efficiency of average 3.2 transformants/${\mu}g$ DNA. To develop a screening system using phytotoxicity of FA, eleven various grains and vegetable seeds were tested for germination in cultures containing FA: Kimchi cabbage seed was selected as the most sensitive host. Screening for FA non-producer of F. oxysporum was done by growing each fungal REMI transformant in Czapek-Dox broth for 3 weeks at $25^{\circ}C$ then observing if the Kimchi cabbage seeds germinated in the culture filtrate. Of more than 5,000 REMI transformants screened, fifty-three made the seeds germinated, indicating that they produced little or fewer FA. Among them, twenty-six were analyzed for FA production by HPLC and two turned out to produce less than 1% of FA produced by a wild type strain. Sequencing of genomic DNA regions (252 bp) flanking the vector insertion site revealed an uncharacterized genomic region homologous (93%) to the F. fujikuroi genome. Further study is necessary to determine if the vector insertion sites in FA-deficient mutants are associated with FA production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.1
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• pp.8-17
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• 2018

Pre-harvest sprouting (PHS) refers to seed germination during ripening, due to loss of dormancy before harvest. As PHS in rice causes decrease in grain yield and quality, tolerance to PHS is an important trait of Japonica cultivars in Korea. It is important to investigate the related genes and environmental factors, because PHS is a quantitative trait. In this study, we examined PHS rates at three different times according to the cumulative daily mean temperature after heading (CTAH) for 5 rice cultivars released in Korea for 5 years from 2013 to 2017 to determine the effect of environmental factors on PHS. ABA content in ripening spikelets was analyzed to understand how it was related to PHS tolerance. PHS rate increased as CTAH increased from $800^{\circ}C$ to $1200^{\circ}C$. PHS rate was significantly different (p < 0.001) among the cultivars, showing Dasanbyeo, Jounbyeo, and Nampyeongbyeo to be PHS-tolerant, and Jopyeongbyeo and Gopumbyeo to be susceptible at all the CTAH of 800, 1000, and $1200^{\circ}C$. In 2015 and 2016, PHS rates were relatively higher, because of high temperature and frequent rainfall during the ripening period. In each cultivar, ABA content decreased as CTAH increased from $800^{\circ}C$ to $1200^{\circ}C$. However, there was no significant correlation between ABA content and PHS tolerance among the cultivars.

• Development and Reproduction
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• v.15 no.2
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• pp.179-185
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• 2011

Some phytoestrogens in soy and red wine, for example, might have beneficiary rather than adverse effects. In particular, dietary soy intake seems to be highly correlated with protection of breast cancer, osteoporosis and cardiovascular disorders. However, questions persist on the potential adverse effects of the main soy constituent genistein (GS) on female reproductive physiology. Previously we found that prepubertal exposure to GS could activate the reproductive system of immature female rats leading to precocious puberty onset, and intracerebroventricularly (ICV) injected GS could directly activate hypothalamic kisspeptin-GnRH neuronal circuits in adult female rats. The present study was performed to examine the hypothalamus-specific GS effects in prepubertal female rats and which subtype of estrogen receptor is mediated in this GS effect. Prepubertal female rats (PND 30) were anaesthetized, treated with single dose of GS (3.4 ${\mu}g$/animal), and sacrificed at 2 hrs post-injection. To determine the transcriptional changes of reproductive hormone-related genes in hypothalamus, total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). ICV infusion of GS significantly lowered the transcriptional activities of mTOR (1:$0.361{\pm}0.058$ AU, p<0.001) but increased that of GAD67 (1:$1.285{\pm}0.099$ AU, p<0.05), which are known to act as an upstream modulator of kisspeptin and GnRH neuronal activities in the hypothalamus, respectively. GS administration enhanced significantly the mRNA levels of KiSS-1(1:$1.458{\pm}0.078$ AU, p<0.001), and exerted no effect on the mRNA level of kisspeptin receptor GPR-54 (1:$1.29{\pm}0.08$ AU). GnRH gene expression was significantly decreased in GS-treated group compared to control group (1:$0.379{\pm}0.196$ AU, p<0.05). There was no difference in the mRNA level of $ER{\alpha}$ in the GS-treated group compare to control group (1:$1.180{\pm}0.390$ AU, Fig. 3A). However, icv infusion of GS significantly increased the transcriptional activities of $ER{\beta}$ (1:$4.209{\pm}0.796$ AU, p<0.01, Fig. 3B). Taken together, the present study indicated that the acute exposure to GS could directly alter the hypothalamic GnRH modulating system in prepubertal female rats. Our study strongly suggested the involvement of $ER{\beta}$ pathway in GS's hypothalamus-specific action, and this idea is consistent with the GS's well-known $ER{\beta}$-mediated protective action in breast cancer.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.355-362
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• 2016

The phosphomannomutase/phosphoglucomutase gene (pmm/pgm) of Vibrio anguillarum (the causative agent of fish vibriosis) was cloned, and the open reading frame corresponded to a protein with 446 amino acids. The pmm/pgm gene showed a significant degree of sequence homology with the previously reported genes from V. mimicus, V. vulnificus, V. splendidus, and V. harveyi, with 92.3%, 91.4%, 89.9%, and 89.9% amino acid identity, respectively. By reverse transcriptase-polymerase chain reaction, we found that the pmm/pgm gene was upregulated under cold stress condition. The PMM/PGM protein is known to catalyze the interconversion between mannose-1-phosphate and mannose-6-phosphate or glucose-1-phosphate and glucose-6-phosphate, which are important intermediates for lipopolysaccharide (LPS) biosynthesis. To confirm the role of PMM/PGM in the LPS biosynthetic pathway, we constructed a knock out mutant by homologous recombination. The respective LPSs were isolated from the V. anguillarum wild-type and mutant strains, and changes were compared by subjecting them to sodium dodecyl sulfate polyacrylamide gel electrophoresis. Based on the different patterns of the LPSs, we expect the pmm/pgm gene to have an important role in LPS biosynthesis. The pmm/pgm-deficient mutant of V. anguillarum will contribute to further studies about the role of LPS in V. anguillarum pathogenesis.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.380-387
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• 2016

This study was performed to select potentially available biological control agent from soil bacteria for prevention of ginseng damping off. More than five hundred strains were isolated from ginseng rhizosphere soil. By testing antifungal activity, we have selected three soil bacteria strains and their ability to produce antibiotics and lytic enzymes such as cellulase, protease and pectate lyase was examined. Also, the presence of genes for biosynthesis of lipopeptide such as fengycin, bacillomycin D, surfactin, iturin A, and zwittermicin A was investigated in selected strains. All three strains produced cellulase, protease, and xylanase. Moreover, these strains had gene for biosynthesis of bacillomycin D, surfactin, and iturin A. ES1 and ES3 strains were identified Bacillus methylotrophucus and ES2 was confirmed Bacillus amyloliquefaciens using phylogenetic analysis on the basis of 16S rRNA gene sequences. In field test, control value of ES1, ES2 and ES3 treatment was 32.4%, 46.8% and 36.7%, respectively. This results indicate that antagonistic microbes with high ability of antifungal and lytic enzyme activity can be used as a useful biological control agent to control ginseng damping off.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.182-187
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• 2012

In this study, the experimental method has been investigated using molecular biological way to identify raw materials from seasoned red-pepper sauce which is one of the most popular spices in Korea. 6 kinds of seasoned red-pepper sauces were chosen as a sample containing chilli pepper, garlic, onion as a major ingredient and species specific primers were used for the identification of the raw material of processed food. Selected samples were pre-treated to remove salt (samples were washed with distilled water 3~4 times for desalting), after that, to amplify the extracted genes, whole genome amplification (WGA) kit was performed. Afterwards, PCR products were confirmed through the electrophoresis. As a result, 102, 180, 280 bp of specific PCR products were confirmed for each major ingredients such as chilli pepper, garlic, onion. From this study, the gene extraction method was validated for the identification of ingredients from the spices and it would be applied to distinction of low quality chilli pepper powder including seasoned red-pepper sauce illegally.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.599-604
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• 2017

The purpose of this study was to explore methods for efficient management of the quality and safety of simple processed agricultural products in Busan. We tested 258 samples of simple processed agricultural products for distribution of aerobic bacteria and coliforms, and identified food-borne pathogens. The average aerobic bacterial and coliforms counts were 7.1 and 4.1 log CFU/g in simple processed vegetables, 6.8 and 3.5 log CFU/g in dried vegetables, and 6.2 and 2.9 log CFU/g in simple processed fruits. Additionally Staphylococcus aureus, Salmonella spp., Campylobacter jejuni/coli and Listeria monocytogenes were not detected in any samples. However, Bacillus cereus, Clostridium perfringens and E. coli were detected in 41 samples (16.3%), 2 samples (0.8%), and 4 samples (1.6%), respectively. This analysis revealed that none of C. perfringens and E. coli isolates harbored pathogenic toxic genes. However, all of B. cereus isolates carried at least 1 toxin gene.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.391-395
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• 2014

Background: We aimed to evaluate the role of genetic polymorphisms in tobacco carcinogen-metabolizing genes and their interactions with smoking in a hospital-based case-control study of Japanese subjects. Materials and Methods: We examine the associations of pancreatic cancer risk with genetic polymorphisms in GSTM1, GSTT1 and GSTP1, phase II enzymes that catalyze the conjugation of toxic and carcinogenic electrophilic molecules. The study population consisted of 360 patients and 400 control subjects, who were recruited from several medical facilities in Japan. Unconditional logistic regression methods were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between genotypes and pancreatic cancer risk. Results: Among the control subjects, the prevalence of the GSTM1-null genotype and the GSTT1-null genotype was approximately 56% and 48%, respectively. Cases and controls were comparable in terms of GSTM1 and GSTT1 genotype distributions. Neither of the deleted polymorphisms in GSTM1 and GSTT1 was associated with the risk of pancreatic cancer, with an age- and sex-adjusted OR of 0.99 (95%CI: 0.74-1.32) for the GSTM1-null genotype, and 0.98 (95%CI: 0.73-1.31) for the GSTT1-null genotype. The OR was 0.97 (95%CI: 0.64-1.47) for individuals with the GSTM1 and GSTT1-null genotypes compared with those with the GSTM1 and GSTT1- present genotypes. No synergistic effects of smoking or GST genotypes were observed. Conclusions: Our results indicate no overall association between the GSTM1 and GSTT1 deletion polymorphisms and pancreatic cancer risk in the Japanese subjects in our study.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.431-438
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• 2006

Purpose : Insulin-like growth factor binding protein(IGFBP)-3 has been known as a tumor suppressor gene, and its anti-tumor function was divided into insulin-like growth factor(IGF)-dependent and IGF-independent mechanism. In IGF-independent mechanism, IGFBP-3 directly interacts with a cell without binding of IGFs, becoming an interesting object in oncology. Several studies demonstrate that one of the well-known tumor suppressor genes, p53, induces directly IGFBP-3 transcription, and the increment of IGFBP-3 expression induces apoptosis of many cancer cells. Recently, the anti-tumor mechanisms of IGFBP-3 have been reported, but post-translational modification of IGFBP-3 and its anti-tumor mechanism are not well known. In this study, we examined whether p53 regulated the glycosylation of IGFBP-3, and analysed the meaning of IGFBP-3 glycosylation related to the apoptosis of cancer cell. Methods : The p53-mutated status of MDA-MB-231 human breast cancer cells was used in this experiment. The expression and glycosylation of IGFBP-3 were tested by Western blot analysis after infection of adenovirus mediated Ad/p53 and/or Ad/IGFBP-3. Results : Ad/p53 infected cells resulted in growth retardation and the induced apoptosis. p53 induced direct expression and glycosylation of IGFBP-3. The increase of glcosylated IGFBP-3 was able to promote cellular apoptosis, and the glycosylation of IGFBP-3 was more activated by the double treatment of Ad/p53 and Ad/IGFBP-3. Conclusion : From this study, the anti-tumor activity of IGFBP-3 was shown to improve the stabilization of IGFBP-3 through the increment of glycosylation of IGFBP-3 by p53. This result suggests that the combined gene therapy of p53 and IGFBP-3 may appropriate treatment of cancer.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.463-470
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• 2016

The enzymatic degradation of xylans is the most versatile way to obtain the high value-added functional compounds or the fermentable sugars for renewable energy. The endo-${\beta}$-xylanases are the major enzymes which hydrolyze the internal ${\beta}$-1,4-linkages of xylan backbones to produce the mixtures of xylooligosaccharides including xylobiose and xylotriose. Among them, glucuronoxylanase GH30 can exclusively hydrolyze the internal ${\beta}$-1,4-linkages of xylans decorated with methylglucuronic acid branches. In the present study, two xylanolytic enzyme (PaXN_10 and PaGuXN_30) genes were cloned from Paenibacillus amylolyticus KCTC 3005, and expressed in Escherichia coli, respectively. PaXN_10 (38.7 kDa) belongs to the endo-${\beta}$-xylanases GH10 family, while PaGuXN_30 (58.5 kDa) is a member of glucuronoxylanase GH30. They share the same optimal reaction conditions at $50^{\circ}C$ and pH 7.0. Enzymatic characterization proposed that P. amylolyticus can utilize the hardwood glucuronoarabinoxylans via the cooperative actions of xylanases GH10 and GH30. The extracellular PaGuXN_30 is secreted into the medium and hydrolyzes glucuronoarabinoxylans to release a series of aldouronic acid mixtures with a methylglucuronic acid branch. The resultant products being transported into the microbial cell are successively degraded into the smaller xylooligosaccharides by the intracellular PaXN_10, which will be utilized for the cellular metabolism.