• The Korean Journal of Mycology
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• v.39 no.3
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• pp.235-238
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• 2011

Agrobacterium harboring vector pCHBs with hygromycin phosphotransferase(hph) and hepatitis B virus surface antigen(HBsAg)gene was transformed into the mycelial culture of Flammulina velutipes. In particular, mild NaOH solution was treated to the mycelia before Agrobacterium infection step. This was purposed to generate putative surface wounds in the mycelial cell walls. The results showed that hygromycin-resistant($hyg^r$) mycelia could be obtained only from NaOH-treated mycelia but not from intact mycelia. The integration of $hyg^r$ gene in fungal genome was confirmed by PCR. In addition, a single transgene integration and heterologous protein expression in F. velutipes could be verified by Southern blot hybridization and western blot analysis, respectively. This study demonstrated an efficient tool for the Agrobacterium-mediated transformation of F. velutipes mycelia.

• The Plant Pathology Journal
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• v.18 no.6
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• pp.301-307
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• 2002

Graft transmission and cytopathological studies of a severe pear disease, pear black necrotic leafspot（PBNLS), were carried out to determine the causal agent of the disease. No evidence was found that a fungal or bacterial pathogen could be the causal agent of the disease. Attempts to transmit the agent by sap-inoculation to other plants including herbaceous hosts failed. How-ever, the pathogen was readily graft-transmitted from symptomatic diseased pears to healthy pears. Graft transmission of the pathogen was also demonstrated by using an indicator plant, PS-95, developed in the laboratory through various grafting methods. Ultrastructural study of the disease revealed the consistent presence of flexuous rod-shaped virus-like particles (VLP) in the symptomatic leaves of both Niitaka cultivar and indicator pear, PS-95. The particles, approximately 12 nm in diameter with undetermined length, occurred in the cytoplasm of mesophyll parenchyma cells. Cells with VLPs also contained fibril-containing vesicles, which are common in cells infected with plant viruses with ssRNA genome. The vesicles were formed at the tonoplast. Based on the symptomatology, the presence of fibril-containing vesicles, and graft-transmissibility, it is believed that the VLPs that occurred on symptomatic leaves of black necrotic leafspot of pear are viral in nature, possibly those of a capillovirus.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.915-921
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• 2001

Phytase improves the bioavailability of phytate phosphorus in plant foods to humans and animals, and reduces the phosphorus pollution of animal waste. In order to express a high level of fungal phytase in Saccharomyces cerevisiae, various expression vectors were constructed with different combinations of promoters, translation enhancers, signal peptides, and terminator. Three different promoters fused to the phytase gene (phyA) from Aspergillus niger were tested: a galactokinase (GAL1) promoter, glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter, and yeast hybrid ADH2-GPD promoter consisting of alcohol dehydrogenase II (ADH2) and a GPD promoter. The signal peptides of phytase, glucose oxidase (GO), and rice amylase 1A(RAmy1A) were included. Plus, the translation enhancers of the ${\Omega}$ sequence and UTR70 from the tobacco mosaic virus (TMV) and spinach, respectively, were also tested. Among the recombinant vectors, pGphyA06 containing the GPD promoter, the ${\Omega}$ sequence, RAmy1A, and GAL7 terminator expressed the highest phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase was also performed by inserting an endoplasmic reticulum (ER) retention signal, KDEL sequence, into the C-terminus of the phytase within the vector pHphyA-6. It appeared that the KDEL sequence directed most of the early expression of phytase into the intracellular compartment yet more than $60\%$ of the total phytase activity was still retained within the cell even after the prolonged (>3 days) incubation of the transformant. However, the intracellular enzyme activity of the transformant without a KDEL sequence was as high as that of the extracellular one, thereby strongly suggesting that the secretion of phytase in S. cerevisiae appeared to be the rate-limiting step for the expression of a large amount of extracellular recombinant phytase, when compared with other yeasts.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.450-457
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• 1998

The cryparin of Cryphonectria parasitica belongs to a cell wall associated fungal hydrophobin. The cryparin, though it is encoded by a single copy gene, is known for the high expression during the liquid culture of C. parasitica, and it turns out that 22% of total mRNA was transcribed for cryparin at 48hr after the liquid culture. In addition, it is also known as one of down-regulated fungal proteins by the presence of double stranded RNA virus, Cryphonectria hypovirus 1. In previous studies (Kim et al., 1999), we have constructed a cryparin-null mutant by replacing the cryparin gene with hygromycin B resistance gene due to site directed homologous recombination. In order for the promoter analysis of cryparin which seems to be very strong as well as mycoviral specific, it is preferable to have a strain with only a target promoter replaced and a discernable target site for incoming vectors. However, the cryparin-null mutant revealed the presence of an additional copy of transforming vector except the one which replaced the cryparin gene. In addition, the cryparin-null mutant did not contain any markers for targeted integration of incoming vectors. This prompts us to design an experiment to obtain a strain for promoter analysis of cryparin gene. A different mating type strain EP6(Mata, $met^-$) was mated with the cryparin-null mutant ${\triangle}$Crp194-7(MatA, Crp${\triangle}$::hph) to make the progenies with only a single replacement vector and $met^-$ characteristic remained. Nutritional assay as well as Southern blot analysis revealed that the progeny, ${\triangle}$Crp194-a6, was the methionine auxotroph with a single replacing vector in genome. Northern blot analysis and PAGE showed that there was no cryparin produced in this bred strain either.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.245-248
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• 2014

Trafficking of viral glycoproteins to the cell surface results in syncytium formation in baby hamster kidney (BHK) cells infected with Newcastle disease virus (NDV). An extract from the medicinal Areca catechu L plant inhibited not only syncytium formation, but also trafficking of the hemagglutinin-neuramidase (HN) glycoprotein to the cell-surface. The viral glycoprotein was processed within the endoplasmic reticulum during transit to the cell membrane. Fungal extracts showed inhibitory activities ($IC_{50}10{\mu}g/mL$) against ${\alpha}$-glucosidase. These results suggested that A. catechu L. extracts inhibited the cell-surface expression of NDV-HN glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.3
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• pp.262-267
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• 2007

Implantation of allografts has increased widely with not only the availability of many allogenic bone but also allogenic soft tissues. The aim of tissue banking is to provide surgeons with safe tissues compatible with their intended clinical application. The incidence of tissue transplant-transmitted infection is unknown and can only be inferred from prospective studies. The possibility of donor-to-recipient disease transmission through soft tissue transplantation can be considered by reviewing the risk associated with other transplanted hard tissues. Viral, bacterial, and fungal infections have been transmitted via transplantation of soft tissue allografts such as skin, cornea, dura, pericardium. fascia lata, and heart valves. Corneas have transmitted rabies, Creutzfeldt-Jakob disease (CJD), hepatitis B (HBV), cytomegalovirus (CMV), herpes simplex virus (HSV), bacteria, and fungi. Heart valves have been implicated in transmitting tuberculosis, hepatitis B. HIV-1 and CMV. CJD has been transmitted by dura and pericardium transplants. Skin has transmitted CMV, bacteria, and fungi. Cadaveric skin, pericardium, dura, and fascia lata have been used in dental patients with intra-oral soft tissue injuries and GBR. This study is review of the considering transmission of infectious disease in allogenic soft tissues and guidelines of reducing the risk. Prior to use, many tissues are exposed to antibiotics, disinfectants, and sterilants, which further reduce or remove the risk of transmitted disease. Because some soft tissue grafts cannot be subjected to sterilization steps, the risk of infectious disease transmission remains and thorough donor screening and testing is especially important.

• Research in Plant Disease
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• v.12 no.3
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• pp.153-157
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• 2006

In 2005, average temperature was lower, and average rainfall was less than those of previous year. The diseases of rice, barley, pepper, chinese melon, apple and oriental pear were surveyed. Bacterial blight, bacterial grain rot, and panicle disease of rice, black rot of pear, and white rot and bitter rot of apple were severe. Especially, brown rot of rice occurred four times higher than those of previous year. Panicle blight of rice increased about 3 times, compared with the previous year, presumed that the higher rainy days, rainfall and RH promoted spread of the fungal pathogens to panicles of rice. The diseases of rice leaf blast, sudden wilt syndrome, downy mildew and powdery mildew of chinese melon in plastic greenhouse, and virus diseases of hot pepper occurred distinctly less than those of the previous year. Another diseases surveyed occurred similar or less.

• Journal of Life Science
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• v.18 no.6
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• pp.804-813
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• 2008

Cordyceps militaris, the Chinese medicinal fungal genus Cordyceps, is reported to possess many pharmacological activities including immunological stimulating, anti-cancer, anti-virus and anti-infection activities. However, the molecular mechanisms of C. militaris on biochemical actions in cancer have not been clearly elucidated yet. In the present study, we investigated the anti-proliferative activity of the water extract of C. militaris (WECM) in human hepatocellular carcinoma HepG2 cells. It was found that WECM could inhibit the cell growth in a dose-dependent manner, which was associated with morphological changes and apoptotic cell death such as formation of apoptotic bodies and increased populations of apoptotic sub-G1 phase. Apoptotic cell death of HepG2 cells by WECM was connected with a up-regulation of pro-apoptotic Bax expression, tumor suppressor p53 and cyclin-dependent kinase inhibitor p21 (WAF1/CIP1). In addition, WECM treatment induced the proteolytic activation of caspase-3 and a concomitant degradation and/or inhibition of poly (ADP-ribose) polymerase (PARP), ${\beta}-catenin$ and phospholipase $(PLC)-{\gamma}1$ protein. Furthermore, caspase-3 inhibitor, z-DEVD-fmk, significantly inhibited WECM-induced apoptosis demonstrating the important role of caspase-3 in the observed cytotoxic effect. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of C. militaris.

• Research in Plant Disease
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• v.11 no.2
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• pp.89-92
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• 2005

In 2004, average temperature was higher, and rainfall was less than those of previous year, The diseases of rice, barley, pepper, chinese melon, apple and oriental pear were surveyed. Seedling diseases, leaf blast, sheath blight and bacterial blight of rice, phytophthova blight, virus diseases and anthracnose of pepper, and sudden wilt syndrome and powdery mildew of chinese melon grown in plastic greenhouse were severe. Especially, sheath blight and bacterial blight of rice occurred two times higher than those of previous year, Panicle blight of rice decreased about 4 times, compared with the previous year, presumed that the lower rainy days, rainfall and RH suppressed spread of the fungal pathogens to panicles of rice. Lower rainfall during mid- and late Aug caused three-times less occurrence of phytophtora blight of red-pepper than that of the previous year, Another diseases surveyed occurred similar or less than those of the previous year.

• Tuberculosis and Respiratory Diseases
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• v.58 no.2
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• pp.167-173
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• 2005

Background : Airborne particles during Yellow Sand phenomena are known to be associated with the respiratory disease. The purpose of this study was to evaluate the concentration and metal component properties of Yellow Sand particles and compare with airborne microbial concentration and species in non Yellow Sand and Yellow Sand phenomena. Methods : Samplings were carried out in 2002 in Seosan, during non Yellow Sand and Yellow Sand phenomena. Samples were taken using the 8-stage Cascade impactor and metallic elements were analyzed by XRF. Those were culture on the media for bacterial and fungal culture and celline for virus. Results : The concentration of total suspended particulate matter were respectively $80.2{\mu}g/m^3$, $40.3{\mu}g/m^3$ in non Yellow Sand and Yellow Sand phenomena. The concentration of metallic elements such as Ca, Fe, Cu and Zn in Yellow Sand phenomena were higher than its in non Yellow Sand. Two bacteria, Bacillus species and Staphylococcus were grown in two periods. In both periods, several fungal spores(Mucor species, Cladosporum, Alternaria, Aspergillus, Penicillium, and Alternaria species) were identified. The differences of bacteria and fungus species not observed in Yellow Sand and non Yellow Sand. Any viruses were not isolated in between both periods. Conclusions : The concentration of total suspended particulate matter and some metallic elements in Yellow Sand phenomena were higher than its in non Yellow Sand. The difference of bacteria and fungus species was not observed in non Yellow Sand and Yellow Sand phenomena.