• Title/Summary/Keyword: specific activity

Search Result 4,403, Processing Time 0.035 seconds

Invertase Production by Fed-batch Fermentations of Recombinant Saccharomyces cerevisiae

  • Koo, Ja-Hyup;Kim, Sang-Yong;Park, Yong-Cheol;Han, Nam-Soo;Seo, Jin-Ho
    • Journal of Microbiology and Biotechnology
    • /
    • v.8 no.3
    • /
    • pp.203-207
    • /
    • 1998
  • Fed-batch fermentations with different feeding media were carried out in order to increase the productivity of invertase expression using a recombinant Saccharomyces cerevisiae containing plasmid pRB58. Two batch cultures showed the expression of the SUC2 gene at a low concentration of glucose, suggesting that glucose concentration could be used as a control variable in a fed-batch operation mode. In the fed-batch culture by feeding the basal medium, cell mass and specific invertase activity did not increase much as compared with the simple batch culture. A series of fed-batch cultures revealed that the sucrose-supplemented medium increased cell mass whereas the enriched medium did specific invertase activity. To capitalize on the synergism of the sucrose-supplemented medium and the enriched medium, the sucrose-supplemented enriched medium was used as a feeding medium. The fed-batch culture using this medium resulted in a 2.4-fold increase in cell mass and a 1.9-fold enhancement in specific invertase activity compared with those of the batch culture. The increase in cell mass and specific invertase activity led to a marked increase in total invertase activity, 250U/ml, which was 6.3 times higher than that of the batch culture.

  • PDF

Purification Efficiency of a Lectin from Maackia fauriei (솔비나무 유래 렉틴의 정제 효율)

  • Bae, Chan-Hyung;Kim, Ju-Cheol;Kim, Yu-Jeong;Kim, Sang-Gu;Na, Kwang-Heum;Park, Byung-Tae;Kim, Ha-Hyung
    • YAKHAK HOEJI
    • /
    • v.51 no.4
    • /
    • pp.259-263
    • /
    • 2007
  • We previously reported the isolation of a sialic acid-specific lectin eluted from the bark of Maackia fauriei using alkaline buffer on a fetuin-affinity column. Application of a borate-based elution buffer in the present study increased the specific activity of purified lectin from crude protein extract by 2.6-fold, whilst only slightly decreasing the recovery by 1.13%. The biological properties of the lectin eluted with borate buffer were the same as those of the lectin eluted with alkaline buffer such as in terms of the hemagglutination activity, hemagglutination inhibition activity, molecular mass, purity, and cytotoxicity to human breast cancer cells. A prepared biotin-labeled lectin conjugate was used to investigate the binding to various glycoproteins. Our results indicate that eluting with borate buffer is more efficient than using alkaline buffer to isolate the lectin adsorbed in a fetuin-affinity column.

Effect of Intracerebroventricular Administration of Ethylcholine Aziridinium (AF64A) on Dopaminergic Nervous Sys-tems

  • Lim, Dong-Koo;Ma, Young;Yi, Eunyoung
    • Archives of Pharmacal Research
    • /
    • v.19 no.1
    • /
    • pp.23-29
    • /
    • 1996
  • Changes in dopaminergic activities were investigated after the intracerebroventricular (icv) administration of ethylcholine aziridium (AF64A) in rats. The levels of dopamine (DA) and metabolites, the activities of tyrosine hydroxylase (TH) and monoamine oxidase (MAO), and the specific binding sites of dopamine receptros in striata, hippocampus, and frontal cortex were assessed 6 days after the AF64A treatment with 3 nmol/each ventrcle. In frontal cortex, the levels of DA and metabolities were significantly decreased without changes in metabolites/DA ratios in the AF64A-treated groups. In contrast, the ratios of metabolites/DA were significantly decreased in striatum and hippocampus in the AF64A treatment. The activity of TH in frontal cortex was significantly decreased. However, that in other areas was not changed. Also the activity of MAO-A was not changed in the studied brain regions. However, the activity of MAO-B in striatum was significantly increased with no change in other areas. The specific binding sites of dopamine D1 and D2 receptors were increased in AF64A-treated frontal cortex. However, those were not changed in striatum and hippocampus except the small decreased specific binding sites of dopamine D-1 receptors in striatum after AF64A treatment. These results indicate that the dopaminergic activity was altered in AF64A treatment. Furthermore, it suggest that the decreased dopaminergic activities in each brain regions might be differently affected by AF64A treatment.

  • PDF

Screening of Leukotriene $B_4$ Receptor Antagonist Activity from the Herbal Drugs (생약의 류코트리엔 $B_4$ 수용체결합 저해작용 검색)

  • Lee, Hwa-Jin;Ryu, Jae-Ha
    • Korean Journal of Pharmacognosy
    • /
    • v.31 no.3
    • /
    • pp.273-279
    • /
    • 2000
  • Leukotriene $B_4\;(LTB_4)$ is a pro-inflammatory mediator synthesized in myeloid cells from arachidonic acid. Elevated levels of $LTB_4$ have been found in a number of inflammatory diseases and levels are related to disease activity in some of these. Because $LTB_4$ interacts with cells through specific cell surface receptors, $LTB_4$ receptor blockade is the most specific approach to reduce the pathogenic role of $LTB_4$. In order to find $LTB_4$ receptor antagonist from plants, we screened the $LTB_4$ receptor antagonistic activity of the methanol extract and solvent fractions of herbal drugs. The ability of samples to inhibit specific binding of $[^3H]-LTB_4$ to human peripheral neutrophils was used as assay to evaluate the antagonistic activity of plant materials. Among the tested methanol extracts of herbal drugs, Mori Radicis Cortex, Perillae Semen, Armeniacae Semen and Sophorae subprostratae Radix showed potent inhibitory activity above 70% at the concentration of $100\;{mu}g/ml$. The inhibitory activities of $LTB_4$ binding to human neutrophils were evaluated for several solvent fractions at three different concentrations. Especially, hexane soluble fractions of Anemarrhenae Rhizoma and Embeliae Radix, and ethyl acetate soluble fractions of Aristolochiae Fructus, Magnoliae Cortex and Zingiberis Rhizoma crudus showed moderate activity at $25\;{mu}g/ml$. These fractions were promising candidates for the study of the activity-guided chromatographic purification of active compounds. Silica gel column chromatography of hexane soluble fractions of Anemarrhenae Rhizoma and Embeliae Radix gave very active sub-fractions, AA-4 and ES-4, and their inhibition activities of $LTB_4$ binding to human neutrophil at $30\;{mu}g/ml$ were 78% and 62%, respectively. From these results we could anticipate new $LTB_4$ receptor antagonist from herbal drugs, and the block of $LTB_4$ effects may provide beneficial in neutrophil mediated diseases such as inflammation and bronchial asthma.

  • PDF

Design of an Activity Recognition System using Smartphone Accelerometer (스마트폰 가속도 센서를 이용한 행위 인식 시스템의 설계)

  • Kim, Joo-Hee;Nam, Sang-Ha;Heo, Se-Kyeong;Kim, In-Cheol
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.2 no.1
    • /
    • pp.49-54
    • /
    • 2013
  • Activity recognition using smartphone accelerometer suffers from the user dependency problem that acceleration patterns of one user differ from those of others for the same activity. Moreover, it also suffers from the position dependency problem since a smartphone may be placed in any pockets or hands. In order to overcome these problems, this paper proposes an effective activity recognition method which is less dependent with both specific users and specific positions of the smartphone. Based on the proposed method, we implement a real-time activity recognition system working on an Android smartphone. Throughout some experiments with 6642 examples collected from different users and different positions, we investigate the performance of our activity recognition system.

In vivo, Immunomodulatory and Antibacterial Reaction of Levamisole in Cultured Eel, Anguilla japonica (Levamisole이 양식뱀장어의 면역조절작용 및 항균효과에 미치는 영향)

  • 최민순;박관하;조정곤
    • Journal of Veterinary Clinics
    • /
    • v.15 no.1
    • /
    • pp.36-40
    • /
    • 1998
  • This experiment was carried out in order to evaluate the immunomodulatory activity of levamisole (LMS) in 5. fgrjn challenged eels with different treatment regimens: 7-day LMS treatment before the challenge, 7-day LMS treatment started simultaneously with the challenge, 14-day treatment before and after the challenge. The antibacterial effect was activated in all treated groups, with the best being obtained in the simultaneously treated group. LMS stimulated the defense mechanisms of the eel as demonstrated by increase in the level of total protein, albumin, trypsin inhibitor capacity, lysozyme activity, antibody titers antibacterial activity and survival rate. These results suggest that antibacterial effects of LMS was achieved by not only non-specific immune response but also specific one in eel.

  • PDF

Studies on Enzyme Activities Responsible for Biosynthesis of Putrescine in Ginseng(Panax ginseng C.A. Meyer) (인삼에서 Putrescine 합성에 관련된 효소활성에 관한 연구)

  • 조병구;조영동
    • Journal of Ginseng Research
    • /
    • v.14 no.1
    • /
    • pp.6-9
    • /
    • 1990
  • Specific activities of ADC and ODC from 2-4 year old ones were higher than that from seedlings whereas those activities were not changed significantly from 2 to 4 years. Generally, activity of ADC was predorminant compared to that of ODC. Free arginine content in roots was much higher than that of leaves. And arginase specific activity from roots was higher than that of leaves. Cumulative results suggest that putrscine formation from ornithine in roots may be more effective than leaves and contribute to putrescine biosynthesis to some extract.

  • PDF

Exact Activity Overlapping Method for Time-cost Tradeoff

  • Gwak, Han-Seong;Lee, Dong-Eun
    • International conference on construction engineering and project management
    • /
    • 2015.10a
    • /
    • pp.109-110
    • /
    • 2015
  • This paper presents a computational method that identifies an exact set of optimal overlap rates between critical activities to meet job site specific needs by using rework cost-slope. The procedures to compute the exact solution are provided in peudocode algorithm. The method is coded into Exact Concurrent Construction Scheduling system that allows practitioners to make more informed decision in accordance with the site-specific condition involved in the overlapping of critical activities. Test cases verify the validity of the computational method and the usability of the system.

  • PDF

Identification of an Enhancer Critical for the ephirn-A5 Gene Expression in the Posterior Region of the Mesencephalon

  • Park, Eunjeong;Noh, Hyuna;Park, Soochul
    • Molecules and Cells
    • /
    • v.40 no.6
    • /
    • pp.426-433
    • /
    • 2017
  • Ephrin-A5 has been implicated in the regulation of brain morphogenesis and axon pathfinding. In this study, we used bacterial homologous recombination to express a LacZ reporter in various ephrin-A5 BAC clones to identify elements that regulate ephrin-A5 gene expression during mesencephalon development. We found that there is mesencephalon-specific enhancer activity localized to a specific +25.0 kb to +30.5 kb genomic region in the first intron of ephrin-A5. Further comparative genomic analysis indicated that two evolutionary conserved regions, ECR1 and ECR2, were present within this 5.5 kb region. Deletion of ECR1 from the enhancer resulted in disrupted mesencephalon-specific enhancer activity in transgenic embryos. We also found a consensus binding site for basic helix-loop-helix (bHLH) transcription factors (TFs) in a highly conserved region at the 3'-end of ECR1. We further demonstrated that specific deletion of the bHLH TF binding site abrogated the mesencephalon-specific enhancer activity in transgenic embryos. Finally, both electrophoretic mobility shift assay and luciferase-based transactivation assay revealed that the transcription factor Ascl1 bound the bHLH consensus binding site in the mesencephalon-specific ephrin-A5 enhancer in vitro. Together, these results suggest that the bHLH TF binding site in ECR1 is involved in the positive regulation of ephrin-A5 gene expression during the development of the mesencephalon.

Luciferase Assay to Screen Tumour-specific Promoters in Lung Cancer

  • Xu, Rong;Guo, Long-Jiang;Xin, Jun;Li, Wen-Mao;Gao, Yan;Zheng, You-Xian;Guo, You-Hong;Lin, Yang-Jun;Xie, Yong-Hua;Wu, Ya-Qing;Xu, Rui-An
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.11
    • /
    • pp.6557-6562
    • /
    • 2013
  • Objective: Specific promoters could improve efficiency and ensure the safety of gene therapy. The aim of our study was to screen examples for lung cancer. Methods: The firefly luciferase gene was used as a reporter, and promoters based on serum markers of lung cancer were cloned. The activity and specificity of seven promoters, comprising CEACAM5 (carcinoembryonic antigen, CEA), GRP (Gastrin-Releasing Peptide), KRT19 (cytokeratin 19, KRT), SFTPB (surfactant protein B, SP-B), SERPINB3 (Squamous Cell Carcinoma Antigen, SCCA), SELP (Selectin P, Granule Membrane Protein 140kDa, Antigen CD62, GMP) and DKK1 (Dickkopf-1) promoters were compared in lung cancer cells to obtain cancer-specific examples with strong activity. Results: The CEACAM5, DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB promoters were cloned. Furthermore, we successfully constructed recombinant vector pGL-CEACAM5 (DKK1, GRP, SELP, KRT19, SERPINB3 and SFTPB) contained the target gene. After cells were transfectedwith recombinant plasmids, we found that the order of promoter activity from high to low was SERPINB3, DKK1, SFTPB, KRT19, CEACAM5, SELP and GRP and the order for promoters regarding specificity and high potential were SERPINB3, DKK1, SELP, SFTPB, CEACAM5, KRT19 and GRP. Conclusion: The approach adopted is feasible to screen for new tumour specific promoters with biomarkers. In addition, the screened lung-specific promoters might have potential for use in lung cancer targeted gene therapy research.