• Mycobiology
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• 제39권3호
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• pp.143-150
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• 2011

The basidiomycete fungus Cryptococcus neoformans is an important pathogen of immunocompromised people. The ability of the fungus to sense its environment is critical for proliferation and the generation of infectious propagules, as well as for adaptation to the mammalian host during infection. The conserved cAMP/protein kinase A pathway makes an important contribution to sensing, as demonstrated by the phenotypes of mutants with pathway defects. These phenotypes include loss of the ability to mate and to elaborate the key virulence factors capsule and melanin. This review summarizes recent work that reveals new targets of the pathway, new phenotypic consequences of signaling defects, and a more detailed understanding of connections with other aspects of cryptococcal biology including iron regulation, pH sensing, and stress.

• Molecules and Cells
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• 제21권2호
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• pp.197-205
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• 2006

We used cDNA microarrays to monitor the transcriptome of ozone stress-regulated genes (ORGs) in two pepper cultivars [Capsicum annuum cv. Dabotop (ozone-sensitive) and Capsicum annuum cv. Buchon (ozone-tolerant)]. Ozone stress up- or down-regulated 180 genes more than three-fold. Transcripts of 84 of these ORGs increased, transcripts of 88 others diminished, and those of eight either accumulated or diminished at different time points in the two cultivars or changed in only one of the cultivars. 67% (120) of the ORGs were regulated differently in ozone-sensitive and ozone-tolerant peppers, most being specifically up-regulated in the ozone-sensitive cultivar. Many were also represented in the plant defense transcriptome against non-host pathogen infection, and some in the transcriptomes for cold, drought, and salinity stresses.

• IMMUNE NETWORK
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• 제11권6호
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• pp.424-427
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• 2011

The nucleotide-oligomerization domain (NOD) proteins are members of the NOD-like receptor (NLR) family, which are intracellular and cytoplasmic receptors. We analyzed the role of NODs for cytokine production by macrophages infected with intracellular pathogen M. leprae, the causative agent of leprosy. Production of pro-inflammatory cytokines such as IL-$1{\beta}$ and TNF-${\alpha}$ was inhibited in the presence of cytochalasin D, an agent blocking phagocytosis, suggesting that intracellular signaling was, partially, required for macrophage activation to M. leprae infection. Next, we investigated the role of NOD1 and NOD2 proteins on NF-${\kappa}B$ activation and cytokine expression. Treatment with M. leprae significantly increased NF-${\kappa}B$ activation and expression of TNF-${\alpha}$ and IL-$1{\beta}$ in NOD1- and NOD2-transfected cells. Interestingly, their activation and expression were inhibited by cytochalasin D, suggesting that stimulation of NOD proteins may be associated with the enhancement of cytokine production in host to M. leprae.

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.359-363
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• 2007

Because of the importance of the type III protein-secretion system in bacteria-plant interaction, its function in bacterial pathogenesis of plants has been intensively studied. To identity bacterial proteins interacting with Xanthomonas hrp gene products that are involved in pathogenicity, we performed the glutathione-bead binding analysis of Xanthomonas lysates containing GST-tagged Hrp proteins. Analysis of glutathione-bead bound proteins by 1-DE and MALDI-TOF has demonstrated that Avr proteins, RecA, and several components of the type III secretion system interact with HrpB protein. This proteomic approach could provide a powerful tool in finding interaction partners of Hrp proteins whose roles in host-pathogen interaction need further studies.

• Journal of Microbiology
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• 제43권spc1호
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• pp.118-131
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• 2005

Vibrio vulnificus is an opportunistic pathogen of humans that has the capability of causing rare, yet devastating disease. The bacteria are naturally present in estuarine environments and frequently contaminate seafoods. Within days of consuming uncooked, contaminated seafood, predisposed individuals can succumb to sepsis. Additionally, in otherwise healthy people, V. vulnificus causes wound infection that can require amputation or lead to sepsis. These diseases share the characteristics that the bacteria multiply extremely rapidly in host tissues and cause extensive damage. Despite the analysis of virulence for over 20 years using a combination of animal and cell culture models, surprisingly little is known about the mechanisms by which V. vulnificus causes disease. This is in part because of differences observed using animal models that involve infection with bacteria versus injection of toxins. However, the increasing use of genetic analysis coupled with detailed animal models is revealing new insight into the pathogenesis of V. vulnificus disease.

• Journal of Microbiology and Biotechnology
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• 제31권10호
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• pp.1350-1357
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• 2021

Staphylococcus aureus (S. aureus) is a major pathogen that causes human pneumonia, leading to significant morbidity and mortality. S. aureus coagulase (Coa) triggers the polymerization of fibrin by activating host prothrombin, which then converts fibrinogen to fibrin and contributes to S. aureus pathogenesis and persistent infection. In our research, we demonstrate that isovitexin, an active traditional Chinese medicine component, can inhibit the coagulase activity of Coa but does not interfere with the growth of S. aureus. Furthermore, we show through thermal shift and fluorescence quenching assays that isovitexin directly binds to Coa. Dynamic simulation and structure-activity relationship analyses suggest that V191 and P268 are key amino acid residues responsible for the binding of isovitexin to Coa. Taken together, these data indicate that isovitexin is a direct Coa inhibitor and a promising candidate for drug development against S. aureus infection.

• 식물병연구
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• 제27권1호
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• pp.38-44
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• 2021

Xylella fastidiosa is the most damaging pathogen in many parts of the world. To increase diagnostic capability of X. fastidiosa in the field, the loop-mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR) assay were developed to mqsA gene of citrate-synthase (XF 1535) X. fastidiosa and evaluated for specificity and sensitivity. Both assays were more robust than current published tests for detection of X. fastidiosa when screened against 16 isolates representing the four major subgroups of the bacterium from a range of host species. No cross reaction with DNA from healthy hosts or other species of bacteria has been observed. The LAMP and PCR assays could detect 10-4 pmol and 100 copies of the gene, respectively. Hydroxynaphthol blue was evaluated as an endpoint detection method for LAMP. There was a significant color shift that signaled the existence of the bacterium when at least 100 copies of the target template were present.

• Mycobiology
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• 제49권2호
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• pp.122-132
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• 2021

The reexamination of the fungal genus Botryosphaeria on 12 plant species of 10 families was carried out based on molecular phylogenetic analyses using the regions of translation elongation factor 1-α, β-tubulin, DNA-directed RNA polymerase II subunit, and internal transcribed spacer region of rDNA and morphological characteristics. Japanese isolates were divided into five clades and include Botryosphaeria dothidea, B. qingyuanensis, B. sinensis, and Botryosphaeria spp. Two species, B. qingyuanensis and B. sinensis have been newly added to the Japanese mycoflora, but their host plants are not specified. Botryosphaeria tenuispora isolated from Leucothoe fontanesiana and insect galls on fruits of Aucuba japonica has been proposed as a new species.

• Fisheries and Aquatic Sciences
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• 제24권11호
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• pp.370-374
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• 2021

In this paper, we have reported the expression of immune-related gene in a new embryonic cell line (FGBC8) which was established from olive flounder (Paralichthys olivaceus) embryos. To explore the cell biotechnological applicability, the FGBC8 cells were incubated with the several mitogens such as lipopolysaccharide (LPS), polyinosinic-polycytidylic acid (poly I:C), flagellin, and interferon (IFN)-γ. After incubation, the expression of immune-related gene was observed in FGBC8 cells through the quantitative real-time PCR. Our results indicate that FGBC8 cells will serve as a valuable research tool for investigating host-pathogen interactions as well as cell biotechnological applications.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2003년도 춘계 학술발표논문집
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• pp.54-57
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• 2003

Implementation of disease-warning systems often results in substantial reduction of spray frequency (Lorente et al., 2000; Madden et al., 2000). This change reduces the burden of pesticide sprays on the environment and can also delay the development of fungicide and bactericide resistance. To assess the risk of outbreaks of many foliar diseases, it is important to quantify leaf wetness duration(LWD) since activities of foliar pathogen depend on the presence of free water on host crop surface for sufficient periods of time to allow infection to occur.(omitted)