• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.961-964
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• 2006

GDP-mannosyltransferase (GMT) is an enzyme responsible for the addition of a mannose to glucose ($\alpha$[1$\rightarrow$3]) during biosynthesis of the water-soluble branched polysaccharide acetan in Acefobacter species. In an effort to obtain a cellulose-overproducing bacterium, a mutant defective in GMT of Acetobacter xylinum KCCM 10100 was constructed by single crossover homologous recombination using part of the aceA gene encoding GMT amplified by polymerase chain reaction. The GMT-disrupted mutant produced 23% more cellulose, but 16% less water-soluble polysaccharide than those of the wild-type strain. Analysis of the sugar composition by gel permeation chromatography revealed that water-soluble polysaccharides produced by the GMT-defective mutant contained no mannose molecule.

• Journal of Veterinary Science
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• 제22권1호
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• pp.12.1-12.11
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• 2021

Background: Bats have been considered natural reservoirs for several pathogenic human coronaviruses (CoVs) in the last two decades. Recently, a bat CoV was detected in the Republic of Korea; its entire genome was sequenced and reported to be genetically similar to that of the severe acute respiratory syndrome CoV (SARS-CoV). Objectives: The objective of this study was to compare the genetic sequences of SARS-CoV, SARS-CoV-2, and the two Korean bat CoV strains 16BO133 and B15-21, to estimate the likelihood of an interaction between the Korean bat CoVs and the human angiotensin-converting enzyme 2 (ACE2) receptor. Methods: The phylogenetic analysis was conducted with the maximum-likelihood (ML) method using MEGA 7 software. The Korean bat CoVs receptor binding domain (RBD) of the spike protein was analyzed by comparative homology modeling using the SWISS-MODEL server. The binding energies of the complexes were calculated using PRODIGY and MM/GBGA. Results: Phylogenetic analyses of the entire RNA-dependent RNA polymerase, spike regions, and the complete genome revealed that the Korean CoVs, along with SARS-CoV and SARS-CoV-2, belong to the subgenus Sarbecovirus, within BetaCoVs. However, the two Korean CoVs were distinct from SARS-CoV-2. Specifically, the spike gene of the Korean CoVs, which is involved in host infection, differed from that of SARS-CoV-2, showing only 66.8%-67.0% nucleotide homology and presented deletions within the RBD, particularly within regions critical for cross-species transmission and that mediate interaction with ACE2. Binding free energy calculation revealed that the binding affinity of Korean bat CoV RBD to hACE2 was drastically lower than that of SARS-CoV and SARS-CoV-2. Conclusions: These results suggest that Korean bat CoVs are unlikely to bind to the human ACE2 receptor.

• Childhood Kidney Diseases
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• 제8권1호
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• pp.18-25
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• 2004

목 적 : 알포트 증후군은 감각신경성 난청을 동반하는 만성 진행성 유전성 신질환으로, 질환의 경과의 다양성으로 인하여 진행성의 예후인자에 특히 유전학적인 역할에 대한 관심이 커지고 있다. 본 연구에서는 만성 진행성 신질환에서 신부전으로의 진행에 관여하는 것으로 알려진 안지오텐신전환효소 유전자 다형성의 발현빈도 및 병의 진행경과와의 관계를 조사하고, 신부전으로의 진행을 억제하는 치료제로서 안지오텐신전환효소 억제제의 가능성을 알아보고자 하였다. 방 법 : 임상양상 및 신조직검사상 알포트 증후군으로 진단된 12명의 환아와 발병하지 않은 12명의 가족들에서 안지오텐신전환효소 다형성의 빈도를 비교하였다. 대상 환아를 신염의 발생 후 10세 이후까지 정상적인 신기능을 유지하고 있는 신기능 유지군과, 발병 후 10세 이전에 만성신부전으로 진행을 시작한(신기능 유지기간 5년 이하) 조기 신부전 진행군으로 구분하여 신기능 감소의 진행시기와 다형성과의 관계를 비교하였고, 발병이 없는 가족에서 다형성의 빈도 및 양상을 관찰하였다. 정상 대조군으로 고혈압, 신장 혹은 심장질환이 없고, 신질환의 가족력, 안지오텐신전환효소 억제제 혹은 다른 항고혈압제의 사용경력이 없는 소아환자 35명을 정상대조군으로 선정하였다. 결과 : 1) 발병연령은 신기능 유지군이 평균 $3.45{\pm}2.4$세였고, 조기 신부전 진행군이 평균 $4.4{\pm}1.2$세로 의미있는 차이가 없었으며, 남녀비는 각각 5:3, 2:1이었다. 2) 12례의 환아 중 4례(33%)는 10세 이전에 평균 8.9세 이전에 만성신부전으로 진행하여 발병에서부터 평균 4.5년 안에 신부전으로 빠를 진행을 보여주는 조기 신부전 진행군이었고, 8례(67%)는 10세 이후까지 이상 신기능이 유지되는 신기능 유지군으로 발병 이후 평균 10.6년(최소 8년, 최대 15년 이상) 이상 신기능을 유지하고 있었으며, 두 군간의 발병 당시 신기능 및 임상양상의 의미있는 차이는 없었다. 3) 알포트 환자의 안지오텐신전환효소 유전자형태는 II type이 3례(25.0%), ID type이 5례(41.7%). DD type이 4례(33.3%)로 정상대조군의 IItype 44.3%, ID type 40.9%, DD type 14.8%와 비교하여 DD type이 많은 경향을 보였으나 두 군사이의 의미 있는 차이는 없었다. 4) 조기 신부전 진행군 4례 중 3례(75%)에서 DD type을 보였고, 신기능 유지군 8례 중 1례(12.5%)에서 DD type을 보여 두 군간의 의미있는 차이를 보였다(p<0.05). 5) 신질환을 나타내지 않은 가족을 대상으로한 조사에서는 총 12례 중 II type 5례(41.7%), ID type 5례(41.7%), DD type 2례(16.6%)로 역시 정상대조군과 유의한 차이를 보이지 않았으며, 신기능 유지여부와 가족내의 DD발현 빈도는 의미있는 관계가 없었다. 결 론 : 소아 알포트 증후군에서 안지오텐신전환효소 유전자의 다형성의 빈도는 정상대조군에 비하여 의미있는 차이가 없었으나 조기에 신부전으로 진행한 환아에서의 DD genotype의 발현율이 의미있게 높게 나타나, 예후인자로서 가능성을 시사하였으며, 따라서 안지오텐신전환효소 억제제 치료가 신부전으로의 진행을 억제하는데 도움을 줄 수 있을 것으로 생각되었다.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 2002년도 제10회 춘계 심포지움 연제집
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• pp.92-92
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• 2002

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.367-369
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• 2001

Recombinant lipase gene (pYEGA ${\alpha}$ -lip) originated from Bacillus stearothermophillus Ll was overexpressed in Saccharomyces cerevisiae. The lipase gene expression level was compared by controlling a constant specifjc growth rates( ${\mu}$ = 0.03, 0.05, 0.07 and $0.1h^{-1}$. Cell g개wth was successfully controlled at the desired rates by feeding rate of glucose and the formation of by-product or accumulation of the glucose was not observed. Above the growth rate of $0.1h^{-1}$. the desired growth rate could not be achieved caused accumulation of by-products(ethanol). The lipase production increased as the specific growth rate decreased. The specific production rate at the lowest specific growth rater(${\mu}$ =0.03) was above 2- folds than the others.

• Journal of Applied Biological Chemistry
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• 제43권1호
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• pp.1-4
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• 2000

Chloramphenicol acetyl CoA transferase (CAT) and angiotensin- converting enzyme inhibitory peptide (ACEI) were fused to C-terminal region of rice ubiquitin to examine the level of transcripts or enzyme activities in yeast. When two chimeric genes under an inducible Gall promoter control were transformed into Saccharomyces cerevisaie, both CAT and ACE inhibitory activities were enhanced by three to four-fold as compared to those containing no ubiquitin gene. However, the levels of transcripts of ubiquitin fused and un fused genes were not significantly different each other. Therefore, it was suggested that the expression of foreign genes was post-transcriptionally enhanced by fusion of plant ubiquitin in heterologous organisms such as yeast.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.952-959
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• 2007

His-His-Leu (HHL), a tripeptide derived from a Korean soybean paste, is an angiotensin-I-converting enzyme (ACE) inhibitor. We report here a method of producing this tripeptide efficiently by expressing tandem multimers of the codons encoding the peptide in E. coli and purifying the HHL after hydrolysis of the peptide multimers. The HHL gene, tandemly multimerized to a 40-mer, was ligated with ubiquitin as a fusion gene (UH40). UH40 was inserted into vector pET29b; the UH40 fusion protein was then produced in E. coli BL21. The recombinant UH40 protein was purified by cation-exchange chromatography with a yield of 17.3mg/l and analyzed by matrixassisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry and protein N-terminal sequencing. Leucine aminopeptidase was used to cleave a 405-Da HHL monomer from the UH40 fusion protein and the peptide was purified using reverse-phase high-performance liquid chromatography (HPLC) on a C18 HPLC column, with a final yield of 6.2mg/l. The resulting peptide was confirmed to be HHL with the aid of MALDI-TOF mass spectrometry, glutamine-TOF mass spectrometry, N-terminal sequencing, and measurement of ACE inhibiting activity. These results suggest that our production method is useful for obtaining a large quantity of recombinant HHL for functional antihypertensive peptide studies.

• Journal of Microbiology and Biotechnology
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• 제32권9호
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• pp.1098-1102
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• 2022

The placenta is a captivating multifunctional organ of fetal origin and plays an essential role during pregnancy by intimately connecting mother and baby. This study explicates placental pathology and information about 25 placentas collected from the mothers infected with novel coronavirus (SARS-COV-2). So far, congenital transmission of SARS-CoV-2 seems to be remarkably uncommon in spite of many cases of COVID-19 during pregnancy. Out of the 25 placental tissue samples collected, none has shown gene expression of SARS-CoV-2 when confirmed by RT-PCR. At the same time, nasal and throat swab samples collected from newborns of SARS-CoV-2-positive mothers correspondingly tested negative by RT-PCR. The shielding properties of placental barriers against viral infections from mothers to newborns remains a mystery. Major histopathological findings have been recorded as choriodecidual tissue with necrosis, intramural fibrin deposition, chorionic villi with fibrosis, and calcification. Moreover, although recent findings are insufficient to prove direct placental transmission of COVID-19, the abundance of angiotensin-converting enzymes-2 (ACE-2) on the placental surface could potentially contribute to unpleasant outcomes during pregnancy as SARS-CoV-2 gains access to human cells via ACE-2. Finally, the significance of these findings is vague and needs further study.

• 생물정신의학
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• 제24권1호
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• pp.39-44
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• 2017

Objectives Angiotensin-converting enzyme (ACE) gene and plasma levels of cytokines, such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin-4 (IL-4), interleukin-6 (IL-6), interleukin-10 (IL-10), have previously been determined to be associated with depression. The purpose of this study was to investigate the association of plasma levels of ACE and cytokines with recurrent depression. Methods A total of 52 participants (14 male, 38 female, aged $43.9{\pm}14.0years$) were enrolled after being diagnosed with depression by experienced psychiatrists using the Mini International Neuropsychiatric Interview from the outpatient clinic of the Department of Psychiatry, CHA Bundang Medical Center. The participants completed blood sampling, the Hamilton Depression Rating Scale (HAMD), the Beck Depression Inventory, the Beck Anxiety Inventory, and the Scale for Suicidal Ideation. Results ACE plasma levels are higher in patients with recurrent depression ($27.4{\pm}10.4U/L$) than in patients with newly diagnosed depression ($19.1{\pm}7.7U/L$) (p = 0.004). The levels of cytokines, such as $TNF-{\alpha}$, IL-4, IL-6, IL-10, are not significantly different between the two groups. Additionally, the ACE plasma level is negatively correlated with a reduction in the HAMD over six weeks (r = -0.429, p = 0.046, n = 22). Conclusions The current findings show that plasma ACE levels may be associated with recurrent depression and further suggest that the renin-angiotensin system could play a role in recurrent depression.

• 한국식품위생안전성학회지
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• 제32권2호
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• pp.135-140
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• 2017

본 연구는 서울시내에서 시판중인 식육에서 E. faecalis를 분리하고 이 균들의 항생제 내성 패턴, 항생제 유출 펌프 유전자 및 병독성 유전자의 분포를 분석하였다. 총 277개의 식육시료에서 93균주의 E. faecalis 를 분리하였다. 이 균주들의 항생제 내성비율은 ampicillin에는 35.5%, chloramphenicol에 6.4%, ciprofloxacin에 4.3%, eryhtromycin에 18.3%, quinupristin-dalfopristin에 76.3%, tetracycline에 45.2%의 내성이었으며 levofloxacin, teiconplanin 및 vancomycin에는 모든 균이 감수성이었다. 약물 유출펌프인 MFS 타입의 eme(A)와 ABC 타입의 efr(A)유전자는 모든 균주(100%)에서 확인되었으며 efr(B)는 98.9%, lsa는 91.4%의 균주에서 확인되었다. 병독성 인자인 gel(E)는 68.8%, ace는 90.3%, asa1는 47.3%, efaA는 91.4%, esp는 12.9%의 균주에서 확인되었다. 본 연구는 시판 식육에서 분리한 지표 미생물의 하나인 E. faecalis의 항생제 내성, 약물유출 펌프 및 병독서 유전자의 분포를 분석한 연구로 지속적인 모니터링을 하여야 할 것으로 사료된다.