• 제목/요약/키워드: fab E

검색결과 53건 처리시간 0.018초

RNase P-dependent Cleavage of Polycistronic mRNAs within Their Downstream Coding Regions in Escherichia coli

  • Lee, Jung-Min;Kim, Yool;Hong, Soon-Kang;Lee, Young-Hoon
    • Bulletin of the Korean Chemical Society
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    • 제29권6호
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    • pp.1137-1140
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    • 2008
  • M1 RNA, the catalytic subunit of Escherichia coli RNase P, is an essential ribozyme that processes the 5' leader sequence of tRNA precursors (ptRNAs). Using KS2003, an E. coli strain generating only low levels of M1 RNA, which showed growth defects, we examined whether M1 RNA is involved in polycistronic mRNA processing or degradation. Microarray analysis of total RNA from KS2003 revealed six polycistronic operon mRNAs (acpP-fabF, cysDNC, flgAMN, lepAB, phoPQ, and puuCBE) showing large differences in expression between the adjacent genes in the same mRNA transcript compared with the KS2001 wild type strain. Model substrates spanning an adjacent pair of genes for each polycistronic mRNA were tested for RNase P cleavage in vitro. Five model RNAs (cysNC, flgMN, lepAB, phoPQ, and puuBE) were cleaved by RNase P holoenzyme but not by M1 RNA alone. However, the cleavages occurred at non-ptRNA-like cleavage sites, with much less efficiency than the cleavage of ptRNA. Since cleavage products generated by RNase P from a polycistronic mRNA can have different in vivo stabilities, our results suggest that RNase P cleavage may lead to differential expression of each cistron.

후박피(Magnoliae bark)로부터 항충치활성을 갖는 물질의 분리 (Isolation of an Anticariogenic Compound from Magnoliae Bark)

  • 이윤수;박헌주;유재선;박형환;권익부;이현용
    • 한국식품과학회지
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    • 제30권1호
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    • pp.230-236
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    • 1998
  • 충치 원인균인 S. mutans가 생산하는 불용성, 부착성 glucan 합성효소인 GTase의 활성을 저해하는 물질을 생약재로 부터 탐색, 개발하여 기능성 식품 또는 의약품의 소재로 응용하는 것을 목적으로 연구를 수행하였다. 32종의 생약재 추출물에 대하여 GTase 저해활성을 측정한 결과, 후박피에서 가장 높은 활성이 관찰되었다. 후박피 추출물에 대하여 용매분획을 행한 결과 ethylacetate층에 대부분의 활성이 존재하였으므로, 이 획분을 silicagel column chromatography, prep. HPLC 등을 이용하여 더욱 분리, 정제하여 순수한 GTase 저해물질을 분리하였다. 이 물질의 분리수율은 0.013% (w/w)였다. 이 화합물을 UV, FAB-MS 및 NMR spectrometry 등을 이용하여 화학구조의 해석을 실시한 결과 이 물질은 coniferyl alcohol의 중합체로 lignan계 화합물인 4,4'-dihydroxy-3,3'-dimethoxylignan (분자량 330)으로 확인되었다. 이 화합물은 후박피에서는 최초로 확인된 물질이다. 또한 충치 원인균인 S. mutans를 포함한 11종의 구강 미생물에 대한 항균성을 검토한 결과 비교 화합물에 비해 비교적 강력한 활성$(MIC;\;31.3\;{\mu}g/ml)$이 나타났다. 지금까지 후박피는 반하후박탕, 후박삼물탕 등 한방약재의 중요한 원료로 이용되어 왔으며, 복통의 치료효과 및 건위 작용 등이 알려져 있다. 또한 후박피 중에는 diphenyl계 화합물인 magnolol 및 honokiol등이 함유되어 있어 이들 물질이 건위작용을 돕는 것으로 알려져 있을 뿐이다. 따라서 이번에 새롭게 확인된 4,4'-dihydroxy-3,3'-dimethoxylignan이 충치 예방효과를 지니고 있다는 사실은 금후 산업적 응용면에서도 매우 중요한 결과로 여겨져 지속적인 연구가 기대된다.

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An Antifungal Antibiotic Purified from Bacillus megaterium KL39, a Biocontrol Agent of Red-Pepper Phytophthora-Blight Disease

  • JUNG HEE KYOUNG;KIM SANG-DAL
    • Journal of Microbiology and Biotechnology
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    • 제15권5호
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    • pp.1001-1010
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    • 2005
  • Bacillus megaterium KL39, an antibiotic-producing plant growth promoting rhizobacterium (PGPR), was selected from soil. The antifungal antibiotic, denoted KL39, was purified from culture filtrate by column chromatography using Dion HP-20, Silica gel, Sephadex LH-20, and prep-HPLC. Thin layer chromatography, employing the solvent system of ethanol:ammonia:water=8:1:1, showed the $R_{f}$. value of 0.32. The antibiotic KL39 showed a negative reaction with ninhydrin solution, positive with iodine vapor, and also positive with Ehrlich reagent. It was soluble in methanol, ethanol, butanol, and acetonitrile, but insoluble in chloroform, toluene, hexane, ethyl ether, or acetone. Its UV spectrum had the maximum absorption at 208 nm. Amino acid composition, FAB-mass, $^{1}H-NMR,\;^{13}C-NMR$, and atomic analyses showed that the antibiotic KL39 (MW=1,071) has a structure very similar to iturin E. The antibiotic KL39 has a broad antifungal spectrum against a variety of plant pathogenic fungi including Rhizoctonia solani, Pyricularia oryzae, Monilinia froeticola, Botrytis cinenea, Altenaria kikuchiana, Fusarium oxysporum, and F. solani. An MIC value of $10\;{\mu}g/ml$ was determined for Phytophthora capsici. Macromolecular incorporation studies with P. capsici using radioactive [$^{3}H-adenine$] as the precursor, indicated that the antibiotic KL39 strongly inhibits the DNA biosynthesis of the fungal cell. Microscopic observation of the antifungal action showed abnormal hyphal swelling of P. capsici. The purified antibiotic KL39 was very effective for the biocontrol of in vivo Phytophthora-blight disease of pepper.

Prognostic Value of a CYP2B6 Gene Polymorphism in Patients with Acute Myeloid Leukemia

  • Alazhary, Nevin M;Shafik, Roxan E;Shafik, Hanan E;Kamel, Mahmoud M
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권11호
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    • pp.4583-4587
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    • 2015
  • Background: The objectives of this study aimed to detect a CYP2B6 polymorphism in de novo cases of acute myeloid leukemia patients and identify any role in disease progression and outcome. Materials and Methods: DNA was isolated from peripheral blood of 82 newly diagnosed acute myeloid leukemia cases and the CYP2B6 G15631T gene polymorphism was assayed by PCR restriction fragment length polymorphism (PCR-RFLP). Results: The frequency of the GG genotype (wild type) was 48 (58.5%) and that of the mutant type T allele was 34 (41.9%). GT genotype heterozygous variants were found in 28 (34%), and TT genotype homozygous variants in 6 (7.3%) cases. We found no significant association between the CYP2B6 G15631T polymorphism and complete response (CR) (p-value=0.768), FAB classification (p-value=0.51), cytogenetic analysis (p-value=0.673), and overall survival (p-value=0.325). Also, there were no significant links with early toxic death (p-value=0.92) or progression-free survival (PFS) (p-value=0.245). Conclusions: Our results suggest that the CYP2B6 polymorphism has no role in disease progression, therapeutic outcome, patient free survival, early toxic death and overall survival in acute myeloid leukemia patients.

A human monoclonal antibody $F_{ab}$ reactive to oxidized LDL and carbamylated LDL recognizes human and mouse atherosclerotic lesions

  • Jang, Young-Ju;Joo, Hee-Jae;Yang, Jeong-In;Seo, Chang-Won;Chung, Kui-Yea;Lanza, Gregory M.;Zhang, Huiying
    • Animal cells and systems
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    • 제15권4호
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    • pp.259-267
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    • 2011
  • This study was undertaken to produce a $F_{ab}$ fragment of a human monoclonal antibody reactive to oxidized and carbamylated low-density lipoprotein (oxLDL and cLDL) using phage display technology. An analysis of DNA sequences of this $F_{ab}$, termed plaque 15,16-46 $F_{ab}$, revealed that the rearranged $V_H$ was highly mutated. Complementarity-determining regions of the $V_H$ showed a very high R/S ratio and contained many positively charged amino acids. In direct binding and competitive ELISA, the $F_{ab}$ reacted strongly with both MDA-LDL and Cu-oxLDL forms of oxLDL, and also showed high affinity for cLDL. Immunofluorescence and immunohistochemical analyses showed that this $F_{ab}$ positively stained atherosclerotic aortic plaques in $ApoE^{-/-}$ mice as well as those in patients with atherosclerosis. The $F_{ab}$ also showed positive staining in placental decidua from patients with preeclampsia. It is suggested that the plaque 15,16-46 $F_{ab}$ against oxLDL and cLDL might possibly be applicable for developing a diagnostic reagent for both human and rodent animal research to detect and characterize atherosclerotic disease progression in atherosclerotic lesions as well as exploring the pathogenesis of atherogenic diseases such as preeclampsia.

Clinical Impact of Overexpression of FOXP3 and WT1 on Disease Outcome in Egyptian Acute Myeloid Leukemia Patients

  • Assem, Magda M;Osman, Ahmed;Kandeel, Eman Z;Elshimy, Reham AA;Nassar, Hanan R;Ali, Radwa E
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권10호
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    • pp.4699-4711
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    • 2016
  • Background: In the last decade, it has become clear that change of gene expression may alter the hematopoietic cell quiescent state and consequently play a major role in leukemogenesis. WT1 is known to be a player in acute myeloid leukemia (AML) and FOXP3 has a crucial role in regulating the immune response. Objectives: To evaluate the impact of overexpression of WT1and FOXP3 genes on clinical course in adult and pediatric AML patients in Egypt. Patients and methods: Bone marrow and peripheral blood samples were obtained from 97 de novo non M3 AML patients (63 adult and 34 pediatric). Real-time quantitative PCR was used to detect overexpression WT1 and FOXP3 genes. Patient follow up ranged from 0.2 to 39.0 months with a median of 5 months. Results: In the pediatric group; WT1 was significantly expressed with a high total leukocyte count median 50X109/L (p=0.018). In the adult group, WT1 had an adverse impact on complete remission induction, disease-free survival and overall survival (p=0.02, p=0.035, p=0.019 respectively). FOXP3 overexpression was associated with FAB subtypes AML M0 +M1 vs. M2, M4+M5 (p =0.039) and the presence of hepatomegaly (p=0.005). Conclusions: WT1 and FOXP3 overexpression has an adverse impact on clinical presentation, treatment response and survival of pediatric and adult Egyptian AML patients.

양식산 굴로부터 쓴맛 성분의 분리 및 성질 (Isolation and Some Properties of Bitter Taste Compounds from Cultured Oyster, Crassostrea gigas)

  • 이종수
    • 한국수산과학회지
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    • 제28권1호
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    • pp.98-104
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    • 1995
  • 1989년 11월부터 1990년 1월 사이에 전남 가막만에서 채취한 양식 굴 및 이를 원료로 제조된 훈제 기름담금 통조림, 보일드 통조림에서 강한 쓴맛이 나타나 품질상 문제가 발생하였는바, 본 연구에서는 이러한 쓴맛의 원인 물질을 규명하고저 시도하였다. 이들 시료의 아세톤 추출액을 액-액 분배, 알루미나, 규산 및 ODS 등의 각종 칼럼을 이용하여 정제한 결과, 5개의 쓴맛성분을 분리하였으며, 이들은 질량분석(FAB-MS)으로 부터 분자량이 각각, OY-22 : 837, OY-23 : 851, OY-24 : 821, OY-25, OY-26 : 835 이었으며, proton NMR spectrum 및 각종 기기분석 결과, 6-7개의 아미노산으로 이루어진 환상 peptide로 추정되었다. 또한, 아미노산 분석으로부터 OY-24에서는 Val, Leu 이, OY-25에서는 Leu, Ile이, OY-26에서는 Leu, Leu이 각각 확인되었으며, 나머지는 이상 아미노산으로 생각되었다. 이들 성분들은 마우스에 대하여 급성독성은 없었으며 $(100{\mu}g/20g\;mice,\;I.p.)$, Asp. niger E. coli, Bac. subtilis 에 대하여는 항균성도 없었다$(10{\mu}g/disk).$ 현재, 각종 생리활성 및 정확한 구조를 검토 중에 있다.

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꽃송이버섯(Sparassis crispa) 자실체로부터 ergosteol peroxide의 분리 및 동정 (Ergosterol peroxides from the fruit body of Sparassis crispa)

  • 이영근;;김형근;이대영;이승은;김금숙;백남인
    • Journal of Applied Biological Chemistry
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    • 제59권4호
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    • pp.313-316
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    • 2016
  • 꽃송이 버섯(S. crispa)을 80 % MeOH 수용액으로 추출하고, 추출물을 EtOAc, n-butyl alcohol 및 물 분획으로 나누었다. EtOAc 분획과 n-BuOH 분획에 대해 $SiO_2$ 및 ODS column chromatography를 반복적으로 실시하여 2종의 ergosterol peroxide를 분리, 정제하였다. infrared spectrometry, nuclear magnetic resonance 및 FAB-MS data를 해석, 화합물 1과 2를 ergosterol peroxide와 3-O-${\beta}$-D-glucopyranosyl ergosterol peroxide로 각각 구조동정 하였다. 두 화합물 모두 꽃송이 버섯으로부터는 이번 실험에서 처음으로 분리되었다.

The inflammatory activity of purified-ferulic acid from Tetragonia tetragonioides

  • Kim, Na-Hyeon;Park, Hye-Jin;Lee, Eun-Ho;Cho, Eun-Bi;Kang, In-Kyu;Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • 제62권3호
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    • pp.239-246
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    • 2019
  • In this study, an evaluation of the anti-inflammatory effect of ferulic acid isolated from Tetragonia tetragonioides in lipopolysaccharide (LPS) simulated RAW 264.7 cells was made. The chemical structure of the active compound was elucidated by $^1H$-NMR, $^{13}C$-NMR, and FAB-MS, and was confirmed to be ferulic acid. Ferulic acid was purified via open column chromatography with Sephadex LH-20 and MCI gel CHP-20. To test the anti-inflammatory effect of ferulic acid, LPS-stimulated RAW 264.7 cells were treated in subsequent experiments with different concentrations of ferulic acid (5, 10, and $25{\mu}g/mL$) and the levels of inflammatory cytokines and enzymes were also measured by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. Cell viability was above 95% at acid concentrations ranging from $5-25{\mu}g/mL$. The results showed that 30% of the production of nitric oxide and 66% of prostaglandin $E_2$ were inhibited by $25{\mu}g/mL$ of ferulic acid, it also inhibited the protein expression of both inducible nitric oxide synthase and cyclooxygenase-2 by 70%. Additionally, it inhibited the production of the pro-inflammatory cytokines, tumor necrosis factor-${\alpha}$, interleukin-6, and interleukin-$1{\beta}$ by 40, 75, and 77%, respectively. According to these results, the anti-inflammatory activity of ferulic acid was demonstrated via his implication in the inhibition of the expression and secretion of inflammatory substances in LPS-stimulated RAW 264.7 cells. Therefore, we concluded that ferulic acid can be used as a functional additive having anti-inflammatory activity.

옥수수 수염에서 Maysin 및 유사물질의 동정 (Identification of Maysin and Related Flavonid Analogues in Corn Silks)

  • 김선림;;김이훈;박철호
    • 한국작물학회지
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    • 제45권3호
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    • pp.151-157
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    • 2000
  • 옥수수수염에 함유되어 있는 maysin 및 유사 flavonoid 물질의 분리 및 정제법을 확립하여 신품종 육성의 기초적인 자료를 제공하고자 본 시험을 수행하였으며 얻어진 결과를 요약하면 다음과 같다. 1. Preparative $C_{18}$ 컬럼에서 10% MeOH에 용출된 물질은 neochlorogenic acid, chlorogenic acid 및 4-caffeoylquinic acid였으며 30% MeOH로 용출된 물질은 rhamnosyl isoorientin이었고 maysin은 50%의 MeOH에서 용출되었다. 2. Silicic acid 컬럼으로 maysin 조추출물의 1차 정제시 100% ethyl acetate 500$m\ell$로 컬럼에 흡착되어 있는 maysin을 용출시켰으며, 이때 수거된 maysin의 순도는 75% 이상에 해당하였고, $C_{18}$ 컬럼($\frac{1}{2}$$\times$43")으로 maysin의 2차 정제시 maysin의 순도는 95% 이상에 달하였다. 3. FAB-MS에 의한 maysin의 분자량은 577M+H m/z이고, fragmentation으로 보아 431M+H m/z은 rhamnose에 해당하였고, $^1$H 및 $^{13}$C NMR에 의한 spectrum을 확인한 결과 분리한 물질이 maysin임을 확인할 수 있었다. 있었다.

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