• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.623-632
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• 2006

To find potential targets of novel antimicrobial agents, we identified essential genes of Staphylococcus aureus N315 by using comparative genomics and allele replacement mutagenesis. By comparing the genome of S. aureus N315 with those of Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Streptococcus pneumoniae, a total of 481 candidate target genes with similar amino acid sequences with at least three other species by >40% sequence identity were selected. of 481 disrupted candidate genes, 122 genes were identified as essential genes for growth of S. aureus N315. Of these, 51 essential genes were those not identified in any bacterial species, and 24 genes encode proteins of unknown function. Seventeen genes were determined as non-essential although they were identified as essential genes in other strain of S. aureus and other species. We found no significant difference among essential genes between Streptococcus pneumoniae and S. aureus with regard to cellular function.

• The Plant Pathology Journal
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• v.27 no.1
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• pp.85-88
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• 2011

Podosphaera fusca (syn. Sphaerotheca fusca, S. fuliginea) is a causal agent of powdery mildew infections on Zinnia elegans, and has been documented in Korea since 1967. An outbreak involving about 1,000 plants in October 2008, in Yangpyeong, Korea, was caused by Golovinomyces cichoracearum. Further surveys of zinnia powdery mildew from 2008-2010 confirmed the widespread occurrence of Zinnia-Golovinomyces association in Korea. Chasmothecia of this fungus have not been found on Z. elegans in Korea. Analysis of internal transcribed spacer rDNA from five Korean collections confirmed the powdery mildew as G. cichoracearum. Comparison with the those from GenBank revealed 100% identity with sequences from zinnia powdery mildew, forming a monophyletic clade with 100% bootstrap support, and with those of G. cichoracearum parasitic on the hosts belonging to the tribe Heliantheae of the family Asteraceae.

• The Korean Journal of Mycology
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• v.45 no.2
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• pp.91-101
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• 2017

Three species of powdery mildew (Erysiphales) on eggplant (Solanum melongena L.) have been listed in Korea, namely Erysiphe cichoracearum (now genus Golovinomyces), Leveillula taurica, and Sphaerotheca fusca (now genus Podosphaera; syn. Podosphaera xanthii). Since E. cichoracearum was recorded on eggplant for the first time in Korea in 1969, it has been regarded as a major powdery mildew agent on that plant. In 1998, the causal agent of powdery mildew on eggplant was recorded as L. taurica, then as S. fusca in 2002. During our extensive field surveys in Korea, we collected 22 samples of eggplant powdery mildews. Our microscopic observations and molecular sequence analyses showed that all of our samples belonged to the genus Podosphaera, in the absence of either E. cichoracearum or L. taurica, suggesting that P. xanthii is the dominant agent of powdery mildew disease on eggplants in Korea. As there have been no additional findings on L. taurica after the first report on the species, it seems to be a minor species that is rarely found in greenhouses. The presence of E. cichoracearum (syn. Golovinomyces cichoracearum s. lat.) on eggplants is questionable, as the morphological characteristics of E. cichoracearum in the original description of the Korean collection deviate from the morphological variations of this species. In addition, no herbarium material of E. cichoracearum remains. Consequently, it seems that P. xanthii is the main species of powdery mildew on eggplants, whereas L. taurica occurs rarely on eggplants, in Korea. This review provides the historical and recent taxonomy of eggplant powdery mildews in detail.

• Research in Plant Disease
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• v.25 no.4
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• pp.220-225
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• 2019

During the year 2018, the symptoms of bunch rot on Shine Muscat (Vitis vinifera L.) were observed in Kimcheon-si, Gyeongbuk province in Korea. The disease appears on the Shine Muscat as a black rot due to prolific fungal sporulation after it has invaded into the Shine Muscat which look completely empty and dryness. Colonies of these fungi are present on the Shine Muscat skin from fruit setting and increase in amount from early season to harvest, while become peak at ripening stage. To isolate the causal agent, small fragments (2 to 3 mm) of decayed tissue from the lesion margin were placed onto potato dextrose agar (PDA) plates. Fungal colonies on PDA produced dense white aerial mycelium and then covered with dark black conidial heads. These heads were large and radiate, and vesicles were globose (2.12-32.0×2.0-3.1 ㎛). Based on morphological and cultural characteristics, this fungus was identified as Aspergillus tubingensis. To confirm its identity, the internal transcribed spacer, β-tubulin, and RNA polymerase II was sequenced for molecular identification. BLAST search indicated 99% identity with A. tubingensis. The pathogenicity test on healthy grape of Shine Muscat produced bunch rot, as the original symptoms. To select effective fungicides for the control of brunch rot, an in vitro antifungal activity of seven fungicides were evaluated against the growth of A. tubingensis. Five fungicides (dipenoconazole, tebuconazole, metconazole, iminoctadine, and captan) exhibited significantly strong suppression of the mycelial growth of A. tubingensis.

• Korean Journal of Cognitive Science
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• v.27 no.3
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• pp.407-420
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• 2016

We live under the consequences of countless decisions, among which significant number of decisions is made by representatives acting on behalf of us. However, individuals often make disparate decisions depending on which identity they are assigned as an agent or with which opponent they are interplaying. In the current research, behavioral discontinuity depending upon actor identity and social relationship was investigated using the ultimatum game. Participants behaved in a more economically rational way when they acted as a group representative compared with when they made decisions as a private individual. However, the direction of the individual-representative discontinuity was reversed when rivalry came into play. Furthermore, more fairness was requested to accept the offers in the interaction with the rival compared with the neutral countergroup. Especially when interacting with the rival group, participants showed contrasting level of decision bias - measured by rejection rate toward unfair offers - according to the degree of mind attribution to the opponent. Specifically, the greater participants attributed a mind to the rival group, the more they rejected the unfair offers from it. The present research is important in that it provides insight into individuals' decision-making in a group context, which sometimes forgoes the financial gain of the entire group and ultimately leads to the sub-optimization of social welfare.

• Journal of Korean Home Economics Education Association
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• v.33 no.2
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• pp.27-44
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• 2021

This study is to identify the concept of action from the critical science perspective and to explore the agency of home economics teachers for the purpose of teacher education. The context and various characteristics of home economics teacher' agency were identified in terms of philosophy and teacher education. The results of the study indicates, first, the concept of action refers to an activity of individuals involving one's own intentions, and include the ability to reveal a unique identity that aims to reach a set purpose and decision, and this can be identified by mutual meaning in the public sphere. Second, teacher agency is influenced by a teacher's professional experiences and cultural and structural aspects, and it can create an environment which can promote self-directed and cooperative relationships among individuals and communities. Therefore, home economics teachers should be able to reasonably judge, contemplate, and act through reflections on the circumstances and consequences in which their agency is exercised. Third, home economics teachers can reflect and think critically about the values, roles, and sense of purpose of home economics education based on agency. Teachers should focus on the process of achieving their agency rather than on completing it, and they can continuously develop it through a perceived shared understanding among teachers. Therefore, the conceptualization of the agency of home economics teachers is to understand the practice revealed in a teacher's actions. This requires environmental support in school settings because it acts as a mechanism for strengthening the thinking and reflection of teachers through the creation of interactive environments in which professional knowledge and experiences can be shared.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.194-198
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• 2015

Enterococcus faecalis is a Gram-positive and facultative anaerobic bacterium that causes many hospital-acquired infections. Novel E. faecalis specific bacteriophage (phage) ECP3 that had been isolated from thirty-four environmental samples and characterized phenotypically and genotypically. ECP3 phage belongs to the family Myoviridae with contractile tail and lysed E. faecalis specifically but other bacteria including Enterococcus faecium. The genome was double-stranded linear DNA and its size was 145,518 bp comprising of 220 open reading frames. The GC content was 35.9%. The genome sequence showed 97% identity in 90% coverage region with Myoviridae phage PhiEF24C. ECP3 is the first E. faecalis-specific Myoviridae phage isolated in Korea which can be a promising antimicrobial agent against E. faecalis infections.

• Journal of Information Processing Systems
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• v.12 no.2
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• pp.196-213
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• 2016

System Architecture Evolution (SAE) with Long Term Evolution (LTE) has been used as the key technology for the next generation mobile networks. To support mobility in the LTE/SAE-based mobile networks, the Proxy Mobile IPv6 (PMIP), in which the Mobile Access Gateway (MAG) of the PMIP is deployed at the Serving Gateway (S-GW) of LTE/SAE and the Local Mobility Anchor (LMA) of PMIP is employed at the PDN Gateway (P-GW) of LTE/SAE, is being considered. In the meantime, the Host Identity Protocol (HIP) and the Locator Identifier Separation Protocol (LISP) have recently been proposed with the identifier-locator separation principle, and they can be used for mobility management over the global-scale networks. In this paper, we discuss how to provide the inter-domain mobility management over PMIP-based LTE/SAE networks by investigating three possible scenarios: mobile IP with PMIP (denoted by MIP-PMIP-LTE/SAE), HIP with PMIP (denoted by HIP-PMIP-LTE/SAE), and LISP with PMIP (denoted by LISP-PMIP-LTE/SAE). For performance analysis of the candidate inter-domain mobility management schemes, we analyzed the traffic overhead at a central agent and the total transmission delay required for control and data packet delivery. From the numerical results, we can see that HIP-PMIP-LTE/SAE and LISP-PMIP-LTE/SAE are preferred to MIP-PMIP-LTE/SAE in terms of traffic overhead; whereas, LISP-PMIP-LTE/SAE is preferred to HIP-PMIP-LTE/SAE and MIP-PMIP-LTE/SAE in the viewpoint of total transmission delay.

• The Plant Pathology Journal
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• v.23 no.2
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• pp.76-89
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• 2007

CaCDPK4, a full-length cDNA clone encoding Capsicum annuum calcium-dependent protein kinase 4, was isolated from chili pepper (Capsicum annuum L.). Deduced amino acid sequence of CaCDPK4 shares the highest homology with tobacco NpCDPK8 and chickpea CaCDPK2 with 79% identity. Genomic blot analyses revealed that CaCDPK4 is present as a single copy in pepper genome, but it belongs to a multigene family. CaCDPK4 was highly induced when pepper plants were inoculated with an incompatible bacterial pathogen. Induced levels of CaCDPK4 transcripts were also detected in pepper leaves by the treatment of ethephon, an ethylene-inducing agent, and high-salt stress condition. The bacterial-expressed GST-CaCDPK4 protein showed to retain the autophosphorylation activity in vitro. GUS expression driven by CaCDPK4 promoter was examined in transgenic Arabidopsis containing transcriptional fusion of CaCDPK4 promoter. GUS expression under CaCDPK4 promoter was strong in the root and veins of the seedlings. GW (-1965) and D3 (-1377) promoters conferred on GUS expression in response to inoculation of an incompatible bacterial pathogen, but D4-GUS (-913) and DS-GUS (-833) did not. Taken together, our results suggest that CaCDPK4 can be implicated on signal transduction pathway of defense response against an incompatible bacterial pathogen in pepper.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.299-305
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• 2012

Petunia hybrida is commonly used in landscapes and interiors for its attractive flower. Virus-like foliar symptoms, including a mosaic with dark green islands surrounding the veins and chlorosis on the leaf margins, were observed on a petunia plant from Icheon, Gyeonggido, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic petunia by serological testing for the presence of CMV coat protein (CP) with a direct antibody-sandwich-enzyme-linked immunosorbent assay. An agent was mechanically transmitted to indicator plant species including Chenopodium quinoa. Examination of the inoculated plant leaves by RT-PCR analysis and electron microscopy revealed the presence of specifically amplified CP products and spherical virions of approximately 28 nm in diameter, respectively, providing confirmation of a CMV infection. Analysis of CP sequences showed that CMV petunia isolate (CMVYJC) shared 82.5-100% amino acid sequence identity with CPs of representative CMV strains. Phylogenetic analysis of CPs supports that CMV-YJC is a member of CMV subgroup IA (CMV-IA) and has biological properties of CMV-IA on host species. To our knowledge, this is the first report of CMV from P. hybrida in Korea.