• The Plant Pathology Journal
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• v.27 no.1
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• pp.26-32
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• 2011

Plant-pathogenic bacteria including Xanthomonas spp. carry genetic diversity in composition of avirulence genes for interaction with their host plants. Previously, we reported genetic diversity of avirulence genes in X. axonopodis pv. glycines. In this study, we determined genetic diversity of five avirulence genes, avrBs1, avrBs2, avrBs3, avrBs4, and avrRxv, in three other Xanthomonas species isolated in Korea by genomic southern hybridization. Although Korean races of X. campestris pv. vesicatoria that were isolated from year 1995 to 2002 had the same avirulence gene patterns as those that already reported, there was race shift from race 3 to race 1 by acquisition of avrBs3 genes. X. campestris pv. campestris isolated from Chinese cabbage, but not from cabbage or radish, carried two avrBs3 genes, and one of them affected HR-eliciting ability of this bacterium in broccoli. X. oryzae pv. oryzae carried eight to thirteen avrBs3 gene homologs, and this bacterium showed dynamic changes of resistance patterns in rice probably by losing or obtaining avrBs3 genes. These results indicate that avrBs3 gene is more diverse in Xanthomonas spp. than other four avirulence genes and also host ranges of these bacteria can be easily changed by loss or acquisition of avrBs3 genes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1034-1037
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• 2002

In this study, we fabricated red organic electrolu-minescent device with a doping material (DCJTB), and The cell structure used ITO:indium tin oxide $[20{\Omega}]$/CuPc:Hole injection layer 20nm/NPB: Hole transfer layer 40nm/$Alq_3$ (host) + DCJTB(1% or 3%) (guest) Emitting layer 40nm/$Alq_3$ : Electron transfer layer 30nm/Al :Cathode layer 150nm. the luminescent layer consisted of a host material. 8-hydrozyquinoline aluminum $(Alq_3)$, and DCJTB dye as the dopant. a stable red emission (chromaticity coordinates : x=0.64, y=0.36) was obtained in this cell with the luminance range of $100-600cd/m^2$. we study the electrical and optical properties of devices.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.14-19
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• 1999

Cucumber mosaic cucumovirus (CMV) is an isometric plant virus with functionally divided genomic RNAs and a broad host range. RNA 1 and RNA 2 each encode one protein, both of which are essential for replication. RNA 3 encodes the viral coat protein and an additional protein thought to be involved in potentiating the cell-to-cell movement of the virus. Functions of the RNAs have been confirmed using a pseudorecombinant virus constructed with infectious cDNA-derived transcripts of the RNAs. Generally, CMV produces different symptoms in various host plants depending on the virus strains. In this mini-review, we describe the potential role of the genes associated with symptom expression of CMV RNAs.

• Korean Journal of Microbiology
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• v.3 no.2
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• pp.22-26
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• 1965

In order to investigate the host range of the mosaic disease of black locust in the Chunchon area, the sap of the mosaic-diseased leaves of black locust itself and the cowpea leaves infected with the above mentioned sap, were inoculated to 53 species of plants belong to 12 families. As to the result, no difference in infection was found as related to the virus sources, and the infection was recognized in 4 species of the family Chenopodiaceae and 8 species of the family Leguminosae. The plants recognized as hosts are as follows: the plants which showed local infection are Chenopodium album, Ch. ambrosioides, Ch. quinoa; the plants which showed systemic infection are Chenopodium amaranticolor, Phaseolus vulgaris, Robinia pseudo-acacia, Vigna sinensis; and Astragalus sinicus, Melilotus indicus, Phaseolus angularis, Pisum sativum and Vicia faba were recognized as carriers. Through investigating its host ranges and symptoms, this mosaic virus of black locust seems not to be regarded as the group of the black locust mosaic virus in southeastern Europe reported by Milinko et al (1961). And, too, it is thought hardly to exist in combination with the cowpea mosaic virus. It appears, therefore, that this mosaic virus was confined to that of black locust.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.249-255
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• 1984

To develop the host-vector system for industrial Coryneform bacteria that seemed to be the most suitable microorganisms for molecular breeding of genes involved in the production of amion acids, nucleotides, and other products of industrial interest, broad host range E. coli plasmid R 1162 DNA was transformed into Brevibacterium ammoniagenes and the plasmids pKU6 isolated from a transformant was physically characterized. All other plasmids from the transformed cells except pKU6 exsisted as multimeric forms in Brevibacterium ammoniagenes. The plasmid DNA was retransformed into Corynebacterium glutamicum with a high frequency ($1.32{\times}10^{-1}$ per cell) and maintained stably both in Brevibacterium ammoniagenes and Corynebacterium glutamicum after 100 generations of cultures with 25-30 copy number per cell. The size of both plasmid pKU6 and plasmid R1162 were the same and restriction maps by EcoR I, Ava I, Pst I, Pvu II and Hinc II were also similar.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.155-159
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• 2023

The Aphis solanella, had been classified as a subspecies of Aphis fabae, is currently recognized as a separated species with A. fabae. The A. solanella is morphologically similar to A. fabae and has the same primary host, but there are differences in the range of the secondary host, physiological and ecological traits, so it has been suggested as a separated species. Since it had not been covered when recording the A. fabae at least including three subspecies in 2006 from South Korea, we recently collected and reconfirmed A. solanella in Busan. Therefore, we report the Aphis solanella as a new record with its description and illustrations.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.246-256
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• 1995

Phenotypic characteristics, pathogenicity and fungicides resistance of fifty one isolates of Botrytis cinerea obtained from various host plants were observed and determined. The relationships between these characteristics were also investigated on the basis of isolation host plants. The isolates of B. cinerea varied in the capacity of sclerotia formation and sporulation. The pathogenicity of 44 isolates from tomato, cucumber, and strawberry was significantly stronger with 3.2 cm in average diameter of necrotic lesions on cucumber leaves than that of seven isolates from other host plants such as orange, gerbera, ginseng, kiwi, grape, pear and from butter with 1.8 cm in average diameter of necrotic lesions. Benomyl resistance of 12 isolates from tomato plants was much higher with the $EC_{50}$, 562 ppm than that of 19 isolates from various host plants. Diethofencarb resistance, however, of 11 isolates from strawberry plants was highest with the $EC_{50}$, 210 ppm among isolates from other host plants. Polygalacturonase activity varied among isolates in the range of 0 to 103 unit and that of isolates from tomato, cucumber and strawberry was slightly lower than that of isolates from other host plants. No significant relationship between pathogenicity and fungicides resistance, polygalacturonase activity was found among 51 isolates of B. cinerea. Isozyme patterns of polygalacturonase produced from two strongly and weakly pathogenic isolates (FC122, KC6) were slightly different depending upon carbon sources during cultivation.

• Parasites, Hosts and Diseases
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• v.42 no.4
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• pp.185-193
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• 2004

Toxoplasma gondii is an obligate intracellular protozoan parasite, which invades a wide range of hosts including humans. The exact mechanisms involved in its invasion are not fully understood. This study focused on the roles of $Ca^{2+}$ in host cell invasion and in T. gondii replication. We examined the invasion and replication of T. gondii pretreated with several calcium modulators, the conoid extrusion of tachyzoites. Calmodulin localization in T. gondii were observed using the immunogold method, and $Ca^{2+}$ levels in tachyzoites by confocal microscopy. In light microscopic observation, tachyzoites co-treated with A23187 and EGTA showed that host cell invasion and intracellular replication were decreased. The invasion of tachyzoites was slightly inhibited by the $Ca^{2+}$ channel blockers, bepridil and verapamil, and by the calmodulin antagonist, calmidazolium. We observed that calcium saline containing A23187 induced the extrusion of tachyzoite conoid. By immunoelectron microscopy, gold particles bound to anti-calmodulin or anti-actin mAb, were found to be localized on the anterior portion of tachyzoites. Remarkably reduced intracellular $Ca^{2+}$ was observed in tachyzoites treated with BAPTA/AM by confocal microscopy. These results suggest that host cell invasion and the intracellular replication of T. gondii tachyzoites are inhibited by the calcium ionophore, A23187, and by the extracellular calcium chelator, EGTA.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.245-251
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• 2015

Alternative hosts increase the difficulty of disease management in crops because these alternate hosts provide additional sources of primary inoculum or refuges for diversity in the pathogen gene pool. Agropyron cristatum (crested wheatgrass), Bromus inermis (smooth bromegrass), Pascopyrum smithii (western wheatgrass), Stipa viridula (green needlegrass), and Thinopyrum intermedium (intermediate wheatgrass), commonly identified in range, prairie, verge, and soil reclamation habitats, serve as additional hosts for Pyrenophora tritici-repentis, the cause of tan spot in wheat (Triticum aestivum L.). A. cristatum (five lines), B. inermis (seven lines), P. smithii (four lines), S. viridula (two lines), and T. intermedium (six lines) were tested for their reactions to 30 representative P. tritici-repentis isolates from races 1-5. Plants were grown until the two-three-leaf stage in a greenhouse, inoculated individually with the 30 isolates, held at high humidity for 24 h, and rated after 7 days. All lines developed lesion types 1-2 (resistant) based on a 1-5 rating scale. Also, leaves from an additional plant set were infiltrated with two host selective toxins, Ptr ToxA as a pure preparation and Ptr ToxB as a dilute crude culture filtrate. All lines were insensitive to the toxins. Results indicate that these grass hosts have a limited or nonsignificant role in tan spot epidemiology on wheat in the northern Great Plains. Additionally, the resistant reactions demonstrated by the grass species in this research indicate the presence of resistance genes that can be valuable to wheat breeding programs for improving wheat resistance to P. tritici-repentis.

• Parasites, Hosts and Diseases
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• v.58 no.3
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• pp.249-255
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• 2020

Toxoplasma gondii, a ubiquitous, intracellular parasite of the phylum Apicomplexa, infects an estimated one-third of the human population as well as a broad range of warm-blooded animals. We have observed that some tyrosine kinase inhibitors suppressed the growth of T. gondii within host ARPE-10 cells. Among them, afatinib, human epithermal growth factor receptor 2 and 4 (HER2/4) inhibitor, may be used as a therapeutic agent for inhibiting parasite growth with minimal adverse effects on host. In this report, we conducted a proteomic analysis to observe changes in host proteins that were altered via infection with T. gondii and the treatment of HER2/4 inhibitors. Secreting proteins were subjected to a procedure of micor basic reverse phase liquid chromatography, nano-liquid chromatography-mass spectrometry, and ingenuity pathway analysis serially. As a result, the expression level of heterogeneous nuclear ribonucleoprotein K, semaphorin 7A, a GPI membrane anchor, serine/threonine-protein phosphatase 2A, and calpain small subunit 1 proteins were significantly changed, and which were confirmed further by western blot analysis. Changes in various proteins, including these 4 proteins, can be used as a basis for explaining the effects of T. gondii infections and HER2/4 inhibitors.