• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.398-406
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• 2022

The outer membrane of Gram-negative bacteria is the outermost layer of cellular environment in which numerous biophysical and biochemical processes are in action sustaining viability. Advances in cell engineering enable modification of bacterial genetic information that subsequently alters membrane physiology to adapt bacteria to specific purposes. Surface display of a functional molecule on the outer membranes is one of strategies that directs host cells to respond to a specific extracellular matter or stimulus. While intracellular expression of a functional peptide or protein fused to a membrane-anchoring motif is commonly practiced for surface display, the method is not readily applicable to exogenous or large proteins inexpressible in bacteria. Chemical conjugation at reactive groups naturally occurring on the membrane might be an alternative, but often compromises fitness due to non-specific modification of essential components. Herein, we demonstrated two distinct approaches that enable site-specific decoration of the outer membrane with a fluorescent agent in Escherichia coli. An unnatural amino acid genetically incorporated in a surface-exposed peptide could act as a chemoselective handle for bioorthogonal dye labeling. A surface-displayed α-helical domain originating from a part of a selected heterodimeric coiled-coil complex could recruit and anchor a green fluorescent protein tagged with a complementary α-helical domain to the membrane surface in a site- and hetero-specific manner. These methods hold a promise as on-demand tools to confer new functionalities on the bacterial membranes.

• Environmental and Resource Economics Review
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• v.31 no.3
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• pp.419-449
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• 2022

This paper aims to quantify the potential economic burdens of EU's carbon border adjustment mechanisms faced by Korean domestic industries. In addition, this study tries to compare and analyzes changes in the burden of each industry resulted from the implementation of the domestic low-carbon policy. Based on the quantitative findings, we intend to suggest policy implications for establishing mid- to long-term strategies in response to climate change risks. Based on the environmentally extended input-output analysis, the total economic burdens of the domestic industries due to the EU's carbon border adjustment mechanisms are estimated to be approximately KRW 8,245.6 billion in 2030. Looking at the impacts by industry, it is found that major industries such as petrochemicals, petroleum refining, transportation equipment, steel, automobiles, and electric/electronic equipment industries are expected to account for 84.3% of the total potential burdens. In addition, in multiple policy scenarios assuming technological developments and energy transition following the implementation of domestic low-carbon policies, the total economic burden of carbon border adjustment is expected to decrease by about 11.7% to 15.0%. The main result of this study suggests that we should not view EU EU's carbon border adjustment mechanism as a trade regulation, but to use it as a momentum for more effective implementation of the low-carbon and energy transition strategies in the global carbon neural era.

• The Journal of Learner-Centered Curriculum and Instruction (JLCCI)
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• v.22 no.1
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• pp.139-170
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• 2018

The Moon Jae-In government's nuclear phase-out policy, on the one hand, has significance in that it has for the first time put the brakes on the nuclear expansion policy and has escaped from the inertia of existing policies. On the other hand, however, since the ethical basis of the nuclear phase-out has not been clearly defined as policy norms, it faces the contradiction between the nuclear phase-out domestically and the export promotion of nuclear power plants. Furthermore the nuclear phase-out policy remains ambiguous and politically irresponsible in that there is no political vision for the energy transition or nuclear phase-out time; and the nuclear phase-out policies have not been enacted yet. This paper considered that these kinds of problems have stemmed from the absence of nuclear politics and analyzed its causes and effects. In this paper the causes of the absence of nuclear politics were identified in the characteristics of the Korean developmental state model and administrative bureaucrats' planning; and its effects were qualitatively analysed through the National Assembly members' statements expressed on the minutes of the relevant National Assembly Standing Committees. The result of the analysis indicates that the lack of nuclear power politics led to the failure of the legislature to control the nuclear administration and led to irresponsible politics especially in the nuclear back-end management. Therefore this research emphasized the necessity of responsible intervention of party politics in the nuclear policy and suggested the policy norms for the nuclear phase-out based on the concepts of Max Weber 's the ethics of conviction (Gesinnungsethik) and the ethics of responsibility (Verantwortungsethik).

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.713-717
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• 2006

$S_2O$-donor macrocyclic isomers incorporating a xylyl group in o- ($L^1$), m- ($L^2$) and p-positions ($L^3$) extract no metal ions except silver(I) from aqueous to chloroform phase. And the magnitudes of %Ex for silver(I) are in the order of $L^1$ > $L^2$ > $L^3$. Taking this result into account, $L^1$-$L^3$ were utilized as membrane active components to prepare potentiometric silver(I)-selective electrodes. The proposed macrocycles-based electrodes E1 ($L^1$), E2 ($L^2$) and E3 ($L^3$) exhibited comparable results which show considerable selectivity toward silver(I) over alkali, alkali earth and other transition metal ions. Comparative NMR study on $L^1$-$L^3$ and their complexes with silver(I) in solution was also accomplished. In addition, a unique sandwich-type complex $[Ag(L^1)_2]CIO_4$ was prepared from the assembly reaction of $L^1$ with $AgClO_4$ and structurally characterized by an X-ray diffraction analysis.

• Korean Journal of Veterinary Service
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• v.39 no.1
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• pp.41-49
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• 2016

In the present study, fast and robust methods for the next generation sequencing (NGS) were developed for analysis of PRRSV full genome sequences, which is a positive sensed RNA virus with a high degree of genetic variability among isolates. Two strains of PRRSVs (VR2332 and VR2332-R) which have been maintained in our laboratory were used to validate our methods and to compare with the sequence registered in GenBank (GenBank accession no. EF536003). The results suggested that both of strains had 100% coverage with the reference; the VR2332 had the coverage depth from minimum 3 to maximum 23,012, for the VR2332-R from minimum 3 to maximum 41,348, and 22,712 as an average depth. Genomic data produced from the massive sequencing capacities of the NGS have enabled the study of PRRSV at an unprecedented rate and details. Unlike conventional sequence methods which require the knowledge of conserved regions, the NGS allows de novo assembly of the full viral genomes. Therefore, our results suggested that these methods using the NGS massively facilitate the generation of more full genome PRRSV sequences locally as well as nationally in regard of saving time and cost.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.62-69
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• 2020

The demand for industrial robots is proliferating with production automation. Industrial robots are used in various fields, such as logistics, welding, and assembly. Generally, six degrees of freedom are required to move freely in space. However, the palletizing robot used for material management and logistics systems typically has four degrees of freedom. In designing such robots, their main parts, such as motors and reducers, need to be adequately selected while satisfying payload requirements and speed. Hence, this study proposes a practical method for selecting the major parts based on dynamic analysis using ADAMS. First, the acceleration torques for the robot motion were found from the analysis, and then the friction torques were evaluated. This study introduces a constant-speed torque constant instead of friction coefficient. The RMS torque and maximum power of each motor were found considering the above torques. After that, this study recommends the major specifications of all motors and reducers. The proposed method was applied to a palletizing robot to verify the suitability of the pre-selected main parts. The verification result shows that the proposed method can be successfully applied to the early design stage of industrial robots.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.229-229
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• 2022

Rapeseed is a crop that is waterlogging sensitive, and it is necessary to breed waterlogging tolerance varieties. Our study presents the comparative transcriptome changes in two rapeseed lines, i.e., waterlogging-tolerant (tJ8634-B-30,) and - sensitive ('EMS26') lines under control and waterlogging stress treatments at the flowering stage. RNA-sequencing analysis revealed 13,279 differentially expressed genes (DEGs) for 'J8634-B-30' and 8,682 DEGs for 'EMS26' under waterlogging stress condition compared to control. Among DEGs of 'J8634-B-30', 6,818 were up-regulated and 6,461 were down-regulated. On the other hand, among the DEGs of 'EMS26', the number of down-regulated genes (5,240) were higher than that of up-regulated genes (3,442). Gene ontology enrichment analysis showed that DEGs related to glucan metabolic, cell wall, and oxidoreductase activity were significantly changed in 'J8634-B-30'. Kyoto Encyclopedia of Genes and Genomes (KEGG)-based analysis in 'J8634-B-30' identified up-regulated DEGs being involved in MAPK signaling pathways. In addition, the DEGs belonging to mechanisms responding to waterlogging stress, i.e., plant hormones, carbon metabolism, Reactive oxygen species (ROS), Nitric oxide (NO) etc. were compared in rapeseed lines. Several DEGs including ethylene-responsive transcription factor (ERF), constitutive triple response (CTR) (in ethylene signaling pathway), monodehydroascorbate Reductase (MDAR), NADPH oxidase (in ROS pathway), cytochrome c oxidase assembly protein (COX) (in NO pathway) up-regulated in 'J8634-B-30'. These outcomes provided the valuable information for further exploring the genetic mechanism of waterlogging tolerance in rapeseed.

• Applied Microscopy
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• v.30 no.2
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• pp.185-191
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• 2000

An unusually large protein complex was found in the cytosol of the hyperthmophilic archaeon. Thermococcus profundus. The purified protein was shown to be a homomultimer of 93 kDa subunit (P93 complex). The complex is extremely heat stable. During 12 hrs incubation with SDS (final concentration 1%) at $85^{\circ}C$, no changed structure could be observed. Electron image analysis of negatively stained showed that the complex has a single, stable characteristic view and a well-preserved core with threefold rotational symmetry. The periphery of the assembly is composed of a nebulose, possibly flexible, component. Based on the projected structure suggest the P93 complex from T. profundus is composed 24 homomultimer.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.411-416
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• 2016

Next-generation sequencing allows the identification of mutations responsible for mutant phenotypes by whole-genome resequencing and alignment to a reference genome. However, when the resequenced cultivar/line displays significant structural variation from the reference genome, mutations in the genome regions absent in the reference cannot be identified by simple alignment. In this review, we report the current status and prospects in identification of genes in mutant phenotypes, by using the methods MutMap, MutMap-Gap, and MutMap+. These methods delineate a candidate region harboring a mutation of interest, followed by de novo assembly, alignment, and identification of the mutation within genome gaps. These methods are likely to prove useful for cloning genes that exhibit significant structural variations, such as disease resistance genes of the nucleotide-binding site-leucine rich repeat (NBS-LRR) class.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.535-543
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• 2014

Backcross breeding is the method most commonly used to introgress new traits into elite lines. Conventional backcross breeding requires at least 4-5 generations to recover the genomic background of the recurrent parent. Marker-assisted backcrossing (MABC) represents a new breeding approach that can substantially reduce breeding time and cost. For successful MABC, highly polymorphic markers with known positions in each chromosome are essential. Single nucleotide polymorphism (SNP) markers have many advantages over other marker systems for MABC due to their high abundance and amenability to genotyping automation. To facilitate MABC in hot pepper (Capsicum annuum), we utilized expressed sequence tags (ESTs) to develop SNP markers in this study. For SNP identification, we used Bukang $F_1$-hybrid pepper ESTs to prepare a reference sequence through de novo assembly. We performed large-scale transcriptome sequencing of eight accessions using the Illumina Genome Analyzer (IGA) IIx platform by Solexa, which generated small sequence fragments of about 90-100 bp. By aligning each contig to the reference sequence, 58,151 SNPs were identified. After filtering for polymorphism, segregation ratio, and lack of proximity to other SNPS or exon/intron boundaries, a total of 1,910 putative SNPs were chosen and positioned to a pepper linkage map. We further selected 412 SNPs evenly distributed on each chromosome and primers were designed for high throughput SNP assays and tested using a genetic diversity panel of 27 Capsicum accessions. The SNP markers clearly distinguished each accession. These results suggest that the SNP marker set developed in this study will be valuable for MABC, genetic mapping, and comparative genome analysis.