• Journal of Microbiology and Biotechnology
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• 제28권9호
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• pp.1482-1492
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• 2018

Fusarium oxysporum trypsin (FOT) is a fungal serine protease similar to mammal trypsin. The FOT could be successfully expressed in Pichiapastoris by engineering the natural propeptide APQEIPN. In this study, we constructed two recombinant enzymes with engineered amino acid sequences added to the N-terminus of FOT and expressed in P. pastoris. The N-terminal residues had various effects on the structural and functional properties of trypsin. The FOT, and the recombinants TE (with peptide YVEF) and TS (with peptide YV) displayed the same optimum temperature ($40^{\circ}C$) and pH (8.0). However, the combinants TE and TS showed significantly increased thermal stability at $40^{\circ}C$ and $50^{\circ}C$. Moreover, the combinants TE and TS also showed enhanced tolerance of alkaline pH conditions. Compared with those of wild-type FOT, the intramolecular hydrogen bonds and the cation ${\pi}$-interactions of the recombinants TE and TS were significantly increased. The recombinants TE and TS also had significantly increased catalytic efficiencies (referring to the specificity constant, $k_{cat}/K_m$), 1.75-fold and 1.23-fold than wild-type FOT. In silico modeling analysis uncovered that the introduction of the peptides YVEF and YV resulted in shorter distances between the substrate binding pocket (D174, G198, and G208) and catalytic triad (His42, Asp102, and Ser180), which would improve the electron transfer rate and catalytic efficiency. In addition, N-terminal residues modification described here may be a useful approach for improving the catalytic efficiencies and characteristics of other target enzymes.

• The Korean Journal of Pain
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• 제31권2호
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• pp.102-108
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• 2018

Background: Nefopam is a non-opioid, non-steroidal analgesic drug with fewer adverse effects than narcotic analgesics and nonsteroidal anti-inflammatory drugs, and is widely used for postoperative pain control. Because nefopam sometimes causes side effects such as nausea, vomiting, somnolence, hyperhidrosis and injection-related pain, manufacturers are advised to infuse it slowly, over a duration of 15 minutes. Nevertheless, pain at the injection site is very common. Therefore, we investigated the effect of warmed carrier fluid on nefopam injection-induced pain. Methods: A total of 48 patients were randomly selected and allocated to either a control or a warming group. Warming was performed by diluting 40 mg of nefopam in 100 ml of normal saline heated to $31-32^{\circ}C$ using two fluid warmers. The control group was administered 40 mg of nefopam dissolved in 100 ml of normal saline stored at room temperature ($21-22^{\circ}C$) through the fluid warmers, but the fluid warmers were not activated. Results: The pain intensity was lower in the warming group than in the control group (P < 0.001). The pain severity and tolerance measurements also showed statistically significant differences between groups (P < 0.001). In the analysis of vital signs before and after the injection, the mean blood pressure after the injection differed significantly between the groups (P = 0.005), but the heart rate did not. The incidence of hypertension also showed a significant difference between groups (P = 0.017). Conclusions: Use of warmed carrier fluid for nefopam injection decreased injection-induced pain compared to mildly cool carrier fluid.

• Applied Biological Chemistry
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• 제38권1호
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• pp.90-94
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• 1995

벼(Oryza sativa L.)를 위시하여 논잡초인 피(Echinochloa crus-galli)와 물달개비(Monochoria vaginalis Presl)에 대한 phenylvinylsulfone유도체(S)들의 제초활성을 측정 한 바, 발아 전후에 벼(Oryza sativa L.)이외의 잡초에 대하여 현저하게 속효성이고 선택적인 제초활성을 나타내었다. (S)의 phenyl기에 X-치환기가 변화함에 따른, 구조와 제초활성과의 관계(SAR)를 양자 약리학적 방법으로 분석한 바, 피의 경우에는 ${\pi}$상수가 클수록(${\pi}$<0) 그리고 LUMO가 음의 값으로 증가할수록 제초활성이 증가 하였다. 한편, 물달개비의 경우에는 ${\pi}$상수의 적정값(optimal value)이 1.10이었으므로 이 값에 가까울수록 제초활성이 클 것이며 HOMO에 의존적임을 알 수 있었다. 따라서 X-치환기로 전자끌게가 치환됨으로써 ${\pi}$상수가 크고(${\pi}$<01.10) 음의 값으로 HOMO와 LUMO가 클수록 고활성을 나타낼 수 있는 화합물의 조건들에 대하여 검토되었으며 실험사실을 합리적으로 설명할 수 있는 제초활성 작용기작(mode of action)을 가정 하였다.

• Journal of Applied Biological Chemistry
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• 제48권1호
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• pp.1-6
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• 2005

Analysis of chlorophyll (Chl) fluorescence implicated treatment of 40 mM NaCl decreased maximal photochemical efficiency of photosystem II (PSII) (Fv/Fm), actual quantum yield of PSII (${\Phi}_{PSII}$), and photochemical quenching (qP) in rice, but increased non-photochemical quenching (NPQ). Decreases in Fv/Fm, ${\Phi}_{PSII}$, and qP were significantly alleviated by $30\;{\mu}M$ jasmonic acid (JA), while NPQ increase was enhanced. Transcription levels of antioxidant isoenzyme genes were differentially modulated by NaCl treatment. Expression of cCuZn-SOD2 gene increased, while those of cAPXb, CATb, and CATc genes decreased. JA prevented salt-induced decrease of pCuZn-SOD gene expression, but caused greater decrease in mRNA levels of cAPXa and Chl_tAPX genes. Investigation of vacuolar $Na^+/H^+$ exchanger (NHX2) and 1-pyrroline-5-carboxylate synthetase (P5CS) gene expressions revealed transcription level of NHX2 gene was increased by JA, regardless of NaCl presence, while that of P5CS gene slightly increased only in co-presence of JA and NaCl. Unlike JA, ${\gamma}$-radiation rarely affected expressions of antioxidant isoenzyme, NHX2, and P5CS genes, except for increase in mRNA level of Chl_tAPX and decrease in that of pCuZn-SOD. These results demonstrate enhanced salt-tolerance in JA-treated rice seedlings may be partly due to high transcription levels of pCuZn-SOD, NHX2, and P5CS genes under salt stress.

• Journal of Microbiology and Biotechnology
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• 제28권11호
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• pp.1846-1849
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• 2018

Recent human gut microbiome studies have supported that the genus Bifidobacterium is one of the most beneficial bacteria for human intestinal health. To develop a new probiotic strain for functional food applications, fourteen fecal samples were collected from healthy Koreans and the strain BCBR-583 was newly selected and isolated from a 25-year-old Korean woman's fecal sample using the selective medium for Bifidobacterium. Subsequent fructose-6-phosphate phosphoketolase (F6PPK) test and 16S rRNA gene sequencing analysis of the strain BCBR-583 confirmed that it belongs to B. longum subsp. longum. The stress resistance tests showed that it has oxygen and heat tolerance activities (5- and 3.9-fold increase for 24 h at 60 and 120 rpm, respectively; $78.61{\pm}6.67%$ survival rate at $45^{\circ}C$ for 24 h). In addition, gut environment adaptation tests revealed that this strain may be well-adapted in the gut habitat, with gastric acid/bile salt resistance ($85.79{\pm}1.53%$, survival rate under 6 h treatments of gastric acid and bile salt) and mucin adhesion ($73.72{\pm}7.36%$). Furthermore, additional tests including cholesterol lowering assay showed that it can reduce $86.31{\pm}1.85%$ of cholesterol. Based on these results, B. longum BCBR-583 has various stress resistance for survival during food processing and environmental adaptation activities for dominant survival in the gut, suggesting that it could be a good candidate for fermented food applications as a new probiotic strain.

• Journal of Microbiology and Biotechnology
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• 제23권11호
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• pp.1493-1499
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• 2013

A novel radiation-resistant Filobasidium sp. yeast strain was isolated from seawater. Along with this strain, a total of 656 yeast isolates were purified from seawater samples collected from three locations in the West Sea of Korea and assessed for their radiation tolerance. Among these isolates, five were found to survive a 5 kGy radiation dose. The most radiation-resistant strain was classified as Filobasidium sp. based on 18S rDNA sequence analysis and hence was named Filobasidium RRY1 (Radiation-Resistant Yeast 1). RRY1 differed from F. elegans, which is closely related to RRY1, in terms of the optimal growth temperature and radiation resistance, and was resistant to high doses of ${\gamma}$-ionizing radiation ($D_{10}$: 6-7 kGy). When exposed to a high dose of 3 kGy irradiation, the RRY1 cells remained intact and undistorted, with negligible cell death. When these irradiated cells were allowed to recover, the cells fully repaired their genomic DNA within 3 h of growth recovery. This is the first report in which a radiation-resistant response has been investigated at the physiological, morphological, and molecular levels in a strain of Filobasidium sp.

• 한국강구조학회 논문집
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• 제27권1호
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• pp.109-118
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• 2015

풍력발전 타워용 원형단면 강재 쉘에 대하여 재료 및 기하학적 비선형 유한요소법으로 극한휨강도 해석을 수행하였다. 쉘의 기하학적 초기변형, 반경 대 두께비, 적용 강종 등이 극한휨강도에 미치는 영향을 분석하였으며, Eurocode 3와 AISI 설계기준에 의한 설계휨강도와 유한요소해석으로 구한 극한휨강도를 비교하였다. 비선형 FE 해석에는 DNV-RP-C202에 제시된 쉘의 좌굴모드와 유로코드에 규정된 진원도 허용오차 및 용접에 의한 변형을 기하학적 초기 결함으로 고려하였다. 원통형 쉘의 반경 대 두께비는 60~210 범위를 고려하였으며 SM520과 HSB800 강재로 제작된 것으로 가정하였다.

• 한국자원식물학회지
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• 제23권6호
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• pp.526-534
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• 2010

Genomes of clusters of related eukaryotes are now being sequenced at an increasing rate. In this paper, we developed an accurate, low-cost method for annotation of gene prediction and exon-intron structure. The gene prediction was adapted for delta 1-pyrroline-5-carboxylate-synthetase (p5cs) gene from China wild-type of the halophytic Leymus chinensis (Trin.), naturally adapted to highly-alkali soils. Due to complex adaptive mechanisms in halophytes, more attentions are being paid on the regulatory elements of stress adaptation in halophytes. P5CS encodes delta 1-pyrroline-5-carboxylate-synthetase, a key regulatory enzyme involved in the biosynthesis of proline, that has direct correlation with proline accumulation in vivo and positive relationship with stress tolerance. Using analysis of reverse transcription-polymerase chain reaction (RT-PCR) and PCR, and direct sequencing, 1076 base pairs (bp) of cDNA in length and 2396 bp of genomic DNA in length were obtained from direct sequencing results. Through gene prediction and exon-intron structure verification, the full-length of cDNA sequence was divided into eight parts, with seven parts of intron insertion. The average lengths of determinated coding regions and non-coding regions were 154.17 bp and 188.57 bp, respectively. Nearly all splice sites displayed GT as the donor sites at the 5' end of intron region, and 71.43% displayed AG as the acceptor sites at the 3' end of intron region. We conclude that this method is a cost-effective way for obtaining an experimentally verified genome annotation.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.74-74
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• 2018

Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. This study was to develop highly polymorphic EST-SSR markers based on cross-species transferability of derived SSRs from switchgrass EST databases and characterize newly developed EST - SSRs to better understand the genetic diversity of collected 37 germplasm accessions of little millet. A total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST - SSR markers were developed based on the trials of transferability of these primers in little millet. The EST - SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. T he average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. T he polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST - SSR markers in assessing genomic relationships in little millet. T he findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

• 소성∙가공
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• 제25권1호
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• pp.36-42
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• 2016

Fiber metal laminates (FMLs) are well known for improved fatigue strength, better impact resistance, superior damage tolerance and slow crack growth rate compared to traditional metallic materials. However, defects and loss of strength of a composite material can occur due to the vertical load from the punch during the joining with a dissimilar material using a conventional clinching method. In the current study, tapered-hole clinching was an alternative process used to join Al 5052 and FMLs. The tapered hole was formed in the FML before the joining. For the better understanding of static and dynamic characteristics, a clinched joining followed by a tensile-shear test was numerically simulated using the finite element analysis. The design parameters were also evaluated for the geometry of the tapered hole by the Taguchi method in order to improve and compare the lateral joining strength of the clinched joint. The influence of the neck thickness and the undercut were evaluated and the contribution of each design parameter was determined. Then, actual experiments for the joining and tensile-shear test were conducted to verify the results of the numerical simulations. In conclusion, the appropriate combination of the design parameters can improve the joining strength and the cross-sections of the tapered-hole clinched joint formed in the actual experiments were in good agreement with the results of the numerical simulations.