• Journal of Microbiology and Biotechnology
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• 제8권1호
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• pp.14-20
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• 1998

Syntheses of the B. stearothermophilus xylanolytic enzymes such as xylanases, ${\beta}$-xylosidases, ${\alpha}$-arabinofurano-sidases, and esterases, were observed to be regulated by the carbon source present in the culture media. Xylan induced synthesis of ${\beta}$-xylosidase at the highest level while xylose gave about 30% of the ${\beta}$-xylosidase activity induced by xylan. The lowest syntheses of the xylanolytic enzymes above mentioned were detected in the basal medium containing glucose as a sole carbon source. When a mixture of xylan and glucose was used as a carbon source, we could observe glucose repression of xylanase (about 70-fold) and ${\beta}$-xylosidase (about 40-fold) syntheses. Whereas, the level of the glucose repression of the expression of the xylA gene encoding the major ${\beta}$-xylosidase of B. stearothermophilus was assessed to be about l0-fold when the relative amounts of the xylA transcript were determined. From the sequence of the xylA gene, we could find two CRE-like sequences (CRE-l: nucleotides ＋124 to ＋136 and CRE-2:＋247 to ＋259) within the reading frame of the xylA gene, either or both of which were suspected to be involved in catabolite repression of the xylA gene.

• Molecular & Cellular Toxicology
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• 제3권1호
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• pp.11-18
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• 2007

Mechanisms of insecticide resistance found in insects may include three general categories. Modified behavioral mechanisms can let the insects avoid the exposure to toxic compounds. The second category is physiological mechanisms such as altered penetration, rapid excretion, lower rate transportation, or increased storage of insecticides by insects. The third category relies on biochemical mechanisms including the insensitivity of target sites to insecticides and enhanced detoxification rate by several detoxifying mechanisms. Insecticides metabolism usually results in the formation of more water-soluble and therefore more readily eliminated, and generally less toxic products to the host insects rather than the parent compounds. The representative detoxifying enzymes are general esterases and monooxygenases that catalyze the toxic compounds to be more water-soluble forms and then secondary metabolism is followed by conjugation reactions including those catalyzed by glutathione S-transferases (GSTs). However, a change in the resistant species is not easily determined and the levels of mRNAs do not necessarily predict the levels of the corresponding proteins in a cell. As genomics understands the expression of most of the genes in an organism after being stressed by toxic compounds, proteomics can determine the global protein changes in a cell. In this present review, it is suggested that the environmental proteomic application may be a good approach to understand the biochemical mechanisms of insecticide resistance in insects and to predict metabolomic changes leading to physiological changes of the resistant species.

• 한국응용곤충학회지
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• 제29권3호
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• pp.170-175
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• 1990

점박이응애(Tetranychus urticae Koch)의 살비제저항성 기작을 구명하기 위한 기초시험으로서, 유기인계 carbophenothion과 ethion, 유기염소계 dicofol, 유기주석계 cyhexatin 및 합성 pyrethroid계 biphenthrin으로 누대도태한 각 저항성계통과 감수성계통을 공시하여, esterase isozyme의 영동대 차이점 (polyacrylamide gel electrophoresis)을 비교한 결과, carbophenothion 저항성계통은 감수성계통에서 나타나지 않은 Est. 1, Est. 3이 검출되었고, ethion과 cyhexatin 저항성계통에서는 각각 Est. 3이, dicofol 저항성계통에서는 Est. 1, Est. 3, Est. 7이, biphenthrin 저항성계통은 Est. 3, Est. 7이 검출되었다. 이러한 영동대와 기질분해량의 차이점으로 미루어 보아 공시살비제들의 저항성발달에는 esterase가 관여하는 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제5권6호
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• pp.335-340
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• 1995

Two types of Rhizoctonia solani esterases induced by cutin hydrolysate were partially purified by ammonium sulfate precipitation and gel filtration. The esterase I with hydrolyzing activity toward both ${\rho}-ni-trophenyl$ butyrate and ${\rho}-nitrophenyl$ palmitate and the esterase II with hydrolyzing activity toward only ${\rho}-ni-trophenyl$ butyrate were inhibited by ebelactone B, an esterase inhibitor produced by actinomycetes with $IC_{50}$ values of 0.01 and $0.09{\;}\mu\textrm{g}/l$, respectively. Spraying on rice seedling with ebelactone B at a concentration of $30{\;}\mu\textrm{g}/ml$ completely suppressed infection by R. solani. Ebelactone B could not protect the wounded rice seedling and did not show any inhibitory effect on the mycelial growth at a concentration of 1 mg/ml. These results indicate that ebelactone B, an esterase inhibitor protects rice plants from infection with R. solani by inhibition of penetration, not through fungitoxic or fungicidal effect.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.121-140
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• 2020

Anaerobic fungi habitat in the gastrointestinal tract of foregut fermenters or hindgut fermenters and degrade fibrous plant biomass through the hydrolysis reactions with a wide variety of cellulolytic enzymes and physical penetration through fiber matrix with their rhizoids. To date, seventeen genera have been described in family Neocallimasticaceae, class Neocallimastigomycetes, phylum Neocallimastigomycota and one genus has been described in phylum Neocallimastigomycota. In National Center for Biotechnology Information (NCBI) database (DB), 23,830 nucleotide sequences and 59,512 protein sequences have been deposited and most of them were originated from Piromyces, Neocallimastix and Anaeromyces. Most of protein sequences (44,025) were acquired with PacBio next generation sequencing system. The whole genome sequences of Anaeromyces robustus, Neocallimastix californiae, Pecoramyces ruminantium, Piromyces finnis and Piromyces sp. E2 are available in Joint Genome Institute (JGI) database. According to the results of protein prediction, average Isoelectric points (pIs) were ranged from 5.88 (Anaeromyces) to 6.57 (Piromyces) and average molecular weights were ranged from 38.7 kDa (Orpinomyces) to 56.6 kDa (Piromyces). In Carbohydrate-Active enZYmes (CAZY) database, glycoside hydrolases (36), carbohydrate binding module (11), carbohydrate esterases (8), glycosyltransferase (5) and polysaccharide lyases (3) from anaerobic fungi were registered. During four decades, 1,031 research articles about anaerobic fungi were published and 444 and 719 articles were available in PubMed (PM) and PubMed Central (PMC) DB.

• 한국동물학회지
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• 제33권3호
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• pp.330-336
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• 1990

배추흰나비의 변태에 따른 esterase의 활성변화 및 zymogram pattern의 변화를 조사하였으며 5령말 유충으로부터 3개의 esterase를 순수 분리하였다. Esterase의 활성은 5령초에서 5령말에 이르는 동안 급격히 증가하여 5령말에서 최대의 활성이 나타났으며 전기영동의 결과 whole body와 중장내 esterase band의 수나 강도는 5령말에서 최대로 나타났다. Gel filtration과 ion-exchange chromatography 및 preparative electorphoresis를 통해 정제된 각 esterase의 최종순도는 약 30-60배였다.

• Mycobiology
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• 제48권2호
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• pp.104-114
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• 2020

The carbohydrate-active enzyme (CAZyme) genes of Trametes contribute to polysaccharide degradation. However, the comprehensive analysis of the composition of CAZymes and the biosynthetic gene clusters (BGCs) of Trametes remain unclear. Here, we conducted comparative analysis, detected the CAZyme genes, and predicted the BGCs for nine Trametes strains. Among the 82,053 homologous clusters obtained for Trametes, we identified 8518 core genes, 60,441 accessory genes, and 13,094 specific genes. A large proportion of CAZyme genes were cataloged into glycoside hydrolases, glycosyltransferases, and carbohydrate esterases. The predicted BGCs of Trametes were divided into six strategies, and the nine Trametes strains harbored 47.78 BGCs on average. Our study revealed that Trametes exhibits an open pan-genome structure. These findings provide insights into the genetic diversity and explored the synthetic biology of secondary metabolite production for Trametes.

• 한국동물학회지
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• 제39권2호
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• pp.190-197
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• 1996

The optimal conditions and substrate specificity of whole body esterase (EST) activity, effects of inhibitors (Eserine, Paraoxon, p-HMB, DDVP, DFP) on the enzyme, and ontogenv of the isozymes were determined in Lucilio ilfustris Meisen. The optimal temperature was $45^{\circ}C$ regardless of kind of reacted substrate, $\alpha-naphthyl$ acetate $(\alpha-Nal,$ a.naphthvl butylate $(\alpha-N),$ and Pnaphthyl acetate $(\beta-Na),$ but the optimal pH showed some regioselectivitv to naphthvl group of the esters; PH 7.0 for Iform, pH 7.5 for a-form. The maximum reaction rate was recorded at about 2.5 $\times$ 10's M of PNa and etNa, but 1.0 $\times$ 10'S M of $\alpha-Nb.$ Among the five EST inhibitors tested, DDVP was the most powerful. However, distinction of the relative specificity of inhibitors between three body parts, head, thorax, and abdomen, was shouts, representing differences in the distribution and activity of isozvmes. Of 12 carboxyl-esterases (CE), 8 cholinesterases (ChE) and 2 arvlesterases (ArE) identified based on their inhibitor specificity throughout the development, two larval and prepupal stage specific ChEs, no pupal specific, and 2 CEs.2ChEs. and one ArE adult specific isozvmes were confirmed.

• Journal of Dairy Science and Biotechnology
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• 제21권2호
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• pp.88-96
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• 2003

Cheese flavor is derived from three main pathways, that are proteolysis, lipolysis and glycolysis, the extent of which varies according to the cheese variety. Proteolysis is the most complex of the three primary events during cheese ripening. The basis of EMC technology is the use of specific enzymes acting at optimum conditions to produce required cheese flavors from suitable substrates. These enzymes consist of proteinases, peptidases, lipases, esterases. The key factors in EMC production are the type of cheese flavor required, the type and specificity of enzyme or cultures used, their concentration and some processing parameters, such as pH, temperature, agitation, aeration, and incubation time. The emulsifiers, bacteriocins, flavor compounds, and precursors also effect to it importantly. The dosage of enzyme or starter culture used is dependent on the intensity of flavor required, processing time and temperature and the quality of the initial substrate. To produce a consistent EMC product it is necessary to have a highly controlled process, and a detailed knowledge of the enzymatic reactions under the conditions used must be fully understood.

• 한국환경농학회지
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• 제14권2호
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• pp.171-178
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• 1995

본 연구는 원제 phosalone (94.4%)에 함유된 불순물들의 동정과 원제 및 정제 phosalone의 in vitro와 in vivo에서의 독성효과를 조사하였다. 원제 phosalone에 대한 GC/MS 분석에서 phosalone oxon, 6-chloro-3-methylthio-2-oxobenzoxazole, 6-chloro-2-oxobenzoxazole, O,O,S-triethylphosphorodithioat (OOSTEPDT), dichlorophosalone 들 5개의 불순물이 동정되었으며, P-NMR 분석에서 OOSTEPDT와 phosalone oxon 등 2종의 불순물이 확인되었다. In vitro에서 원제 Phosalone과 정제 phosalone의 AchE와 BuChE에 대한 $k_i$ 값을 비교한 결과, 원제 phosalone이 정제 phosalone보다 약 10배 빠르게 ChE를 저해하는 것으로 나타났으며, cytosolic esterases에 대해서도 10배 정도 더 강한 저해력을 보였다. In vivo에서도 원제 phosalone이 정제 phosalone 보다 생쥐의 뇌 AChE의 활성을 약 35% 더 저해 하였으며, 쥐의 혈액 erythrocyte AChE와 plasma BuChE 그리고 cytosolic esterases의 활성도 더 심하게 저해하는 것으로 관찰되었다. 이러한 결과는 원제 phosalone 중 함유된 불순물들에 의한 것으로 사료되었으며, 특히 phosalone oxon에 의한 것으로 추정되었다.