• Title/Summary/Keyword: ompA

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Soluble Expression of OmpA from Haemophilus parasuis in Escherichia coli and Its Protective Effects in the Mouse Model of Infection

  • Ahn, Jungoh;Hong, Minhee;Yoo, Sungsik;Lee, Eungyo;Won, Hokeun;Yoon, Injoong;Jung, Joon-Ki;Lee, Hongweon
    • Journal of Microbiology and Biotechnology
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    • v.22 no.9
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    • pp.1307-1309
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    • 2012
  • Haemophilus parasuis causes contagious porcine Gl$\ddot{a}$sser's disease leading to severe losses in the swine industry. In this study, we established an efficient Escherichia coli-based system for the expression of H. parasuis major outer-membrane protein (MOMP) that has been known as a good vaccine candidate against Gl$\ddot{a}$sser's disease. Use of an E. coli-derived pelB leader sequence made it possible to produce recombinant MOMP (rMOMP) as the soluble forms without an additional refolding process. Using two different animal models, it was evaluated that the rMOMP was capable of inducing a significant immune response and providing protection against H. parasuis infection.

Understanding of Interactions Between Acanthamoeba and Escherichia coli on Cell-Based System

  • Jung, Suk-Yul
    • Biomedical Science Letters
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    • v.17 no.3
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    • pp.173-176
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    • 2011
  • Free-living Acanthamoeba are eukaryotic protozoan organisms that are widely distributed in the air, water, etc such as environment. Acanthamoeba ingest the Escherichia coli which will replicate in cytoplasm of Acanthamoeba. Bacterial pathogenicity or virulence is one of important determinant factors to survive in free-living Acanthamoeba and otherwise Acanthamoebic pathogenicity is also an important factor for their interactions. Bacterial association with pathogenic strain of Acanthamoeba T1 and T4 was lower about two times than non-pathogenic T7. Bacterial invasion percentages into T1 were higher about three times than T7 but bacterial survival in T7 was increased as T1. The capsule-deletion mutant exhibited limited ability for invasion/uptake by and survival inside pathogenic Acanthamoeba T4. E. coli-outer membrane protein A (OmpA) decreased bacterial association with A. castellanii by about three times and it had higher effects than lipopolysaccharides (LPS). Under favorable conditions, the mutants were not survived in Acanthamoeba up to 24 h incubation. Therefore, this review will report pathogenic and non-pathogenic Acanthamoeba strains interactions with E. coli and its several mutants, i.e., capsule, OmpA and LPS.

운용 및 유지보수 프로세서

  • 서장원;안규석;이규열
    • Information and Communications Magazine
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    • v.6 no.1
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    • pp.62-68
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    • 1989
  • TDX-1A의 유지보수 및 운용관리 프로세서는 8비트 프로세서 사용에 따른 성능상의 제약과 프로그램 체계상의 문제점이 있어 TDX-1B에서는 호처리에 직접 영향을 미치지 않는 SAP, SMP 및 IOIP를 32비트 프로세서로 통합하여 유지보수 및 운용관리를 체계화함과 동시에 이에 관련된 기능을 보완한 OMP(Operation and Maintenance Processor)를 개발하였다.

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Reweighted L1-Minimization via Support Detection (Support 검출을 통한 reweighted L1-최소화 알고리즘)

  • Lee, Hyuk;Kwon, Seok-Beop;Shim, Byong-Hyo
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.2
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    • pp.134-140
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    • 2011
  • Recent work in compressed sensing theory shows that $M{\times}N$ independent and identically distributed sensing matrix whose entries are drawn independently from certain probability distributions guarantee exact recovery of a sparse signal with high probability even if $M{\ll}N$. In particular, it is well understood that the $L_1$-minimization algorithm is able to recover sparse signals from incomplete measurements. In this paper, we propose a novel sparse signal reconstruction method that is based on the reweighted $L_1$-minimization via support detection.

Analysis of Vibrio parahaemolyticus OMPs and Production of Antibodies against OMPs

  • Kim, Soo-Min;Noh, Bong-Soo;Kim, Hae-Yeong;Park, Se-Jin;Ji, Geun-Eog
    • Food Science and Biotechnology
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    • v.14 no.3
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    • pp.410-412
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    • 2005
  • Vibrio parahaemolyticus is a gram-negative bacterium which acts as a causative agent for food poisoning. Studies with respect to specific extracellular proteins of V. parahaemolyticus would be useful for the development of specific detection methods against V. parahaemolyticus. In our present study, outer membrane proteins (OMPs) of V. parahaemolyticus were obtained from insoluble traction of 1% sarkosyl treated-cell wall materials. SDS-PAGE analysis showed the presence of several conserved outer membrane proteins among five strains of V. parahaemolyticus, and three bands were identified as V. parahaemolyticus OMPs through MALDI-TOF analysis. Polyclonal antibodies enriched with anti-OmpU were obtained from immunized rabbits. The antibodies against these proteins may be useful for the development of detection methods for V. parahaemolyticus.

Signal Processing Logic Implementation for Compressive Sensing Digital Receiver (압축센싱 디지털 수신기 신호처리 로직 구현)

  • Ahn, Woohyun;Song, Janghoon;Kang, Jongjin;Jung, Woong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.21 no.4
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    • pp.437-446
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    • 2018
  • This paper describes the real-time logic implementation of orthogonal matching pursuit(OMP) algorithm for compressive sensing digital receiver. OMP contains various complex-valued linear algebra operations, such as matrix multiplication and matrix inversion, in an iterative manner. Xilinx Vivado high-level synthesis(HLS) is introduced to design the digital logic more efficiently. The real-time signal processing is realized by applying dataflow architecture allowing functions and loops to execute concurrently. Compared with the prior works, the proposed design requires 2.5 times more DSP resources, but 10 times less signal reconstruction time of $1.024{\mu}s$ with a vector of length 48 with 2 non-zero elements.

Post-Processing for JPEG-Coded Image Deblocking via Sparse Representation and Adaptive Residual Threshold

  • Wang, Liping;Zhou, Xiao;Wang, Chengyou;Jiang, Baochen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.3
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    • pp.1700-1721
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    • 2017
  • The problem of blocking artifacts is very common in block-based image and video compression, especially at very low bit rates. In this paper, we propose a post-processing method for JPEG-coded image deblocking via sparse representation and adaptive residual threshold. This method includes three steps. First, we obtain the dictionary by online dictionary learning and the compressed images. The dictionary is then modified by the histogram of oriented gradient (HOG) feature descriptor and K-means cluster. Second, an adaptive residual threshold for orthogonal matching pursuit (OMP) is proposed and used for sparse coding by combining blind image blocking assessment. At last, to take advantage of human visual system (HVS), the edge regions of the obtained deblocked image can be further modified by the edge regions of the compressed image. The experimental results show that our proposed method can keep the image more texture and edge information while reducing the image blocking artifacts.

Studies on biochemical and immunological properties of Aetinobacillus pleuropneumoniae Isolated from the slaughter pigs with respiratory lesions in chungnam province (충남지역 도축돈의 폐병변으로 부터 분리한 Actinob acillus pleuropneumoniae의 생물학적 및 면역학적 특성)

  • 이종훈;안신욱;정영재;장경수;전무형
    • Korean Journal of Veterinary Service
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    • v.20 no.1
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    • pp.103-125
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    • 1997
  • An epidemiologic study on pleuropneumonia in the slaughter pigs(Chonan and Asan area, Chungnam province, Korea) during the period of January 1994 through December 1995 was conducted. Isolation of A pleuropneumoniae was attempted in 425 pigs with pneumonic lesions. Biochemical properties, antimicrobial susceptibility, serotypes and pathogenicity of isolated A pleuropneumoniae were investigated. In addition, outer membrane protein(OMP) of the Isolates were extracted to determine its properties and immunogenicity in both mice and piglets The results obtained through this study were summarized as followed ; 1. Of 3, 395 slaughter pigs, pleuropneumonia was observed in 425 pigs(10.6%). A pleuropneumoniae was isolated from 22 pigs(5.2%) out of 425 pigs with pneumonic lesions. The biochemical properties of all isolates were same as those of reference A pleuropneumoniae strain. Among 22 isolates, 9, 1 and 12 isolates were serovar 2, 3 and 5, respectively. 2. The results of antimicrobial susceptibility test revealed that the isolates showed high susceptibility to ciprofloxacin and cephalothin, moderate susceptibility to amikacin, gentamicin, kanamycin and streptomycin, and low susceptibility to erythromycin, tylosin and sulfadimethoxin. 3. The isolates were varied in pathogenicity to mice. Median lethal dose of LE9402(serovar 2) and LE9511(serovar 5) were $9.2{\times}10^7$ CFU and $2.8{\times}10^7$%CFU, respectively. Specific pneumonic lesions were observed from the infected mice with clinical signs. Bacteria recovery rate was high in the lung, but low In heart blood and tracheas. 4. Serovar 2 was found to be more pathogenic than serovar 5 in guinea pig. Mortality on guinea pigs inoculated with serovar 2($5.4{\times}10^8-5.4{\times}10^6$CFU) and serovar 5($2.8{\times}10^8-2.8{\times}10^6$ CFU) was 20~40% and 40~80%, respectively. A severe hemorrhagic lesions and focal pneumonic lesions were observed from dead guinea pigs. Bacteria recovery rate was relatively higher in the lung than that of other organs. 5. In the SDS-PAGE analysis, OMP-enriched fractions of both isolates and reference strains contain common peptide bands equivalent to molecular weight of 17, 27, 42, 52 and 95Kd. In addition to common peptide bands, the bands which are specific to each isolate were also observed. The profiles of Sephadex G25 fractions showed 3 major peaks. The common peptide bands which were observed by SDS-PAGE of the crude OMPs were found in the peaks 1 and 2. 6. The OMPs extracted from serovar 2(LE9402) and serovar 5(LE9511) provided high level of protection in mice(70~80%) and pigs(100%). All animals inoculated with OMPs were seroconverted, showing micro-agglutination titer of 640 to 1280.

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Expression of the EPO-like Domains of Human Thrombopoietin in Escherichia coli

  • Koh, Yeo-Wook;Koo, Tai-Young;Ju, Sang-Myoung;Kwon, Chang-Hyuk;Chung, Joo-Young;Park, Myung-Hwan;Yang, Jai-Myung;Park, Seung-Kook
    • Journal of Microbiology and Biotechnology
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    • v.8 no.6
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    • pp.553-559
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    • 1998
  • cDNA of human thrombopoietin (hTPO) amplified by polymerase chain reaction from a cDNA library of human fetal liver was cloned. EPO-like domains ($hTPO_{153} \;or\; hTPO_{l63})\; of\; hTPO(hTPO_{332}$) were expressed in Escherichin coli using several kinds of expression systems, such as ompA secretion, thioredoxin fusion, and the $P_L$ and T7 expression systems. To obtain $hTPO_{153}$ in soluble form, $hTPO_{153}$ cDNA was fused in-frame behind the gene encoding ompA signal sequence and thioredoxin protein. When fused with either of the genes, $hTPO_{153}$ was not expressed to the detectable level. However, a high level expression of the EPO-like domain of hTPO was obtained using the PL and T7 expression system. $hTPO_{153} \;or\; hTPO_{l63} cDNA were subcloned into the pLex and pET-28a(+) vectors under the control of the inducible$ P_L\;T_7$ promoter, respectively. Proteins expressed using pl.ex vector and pET-28a(+) detected in insoluble forms with an expression level of about 14% and 9% of total cellular proteins, respectively, and the level of expression was rapidly diminished in 2 h after the maximum level of expression was reached.

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A Study on the Protein Productivity of the Promoters for Cold Inducible Genes in Escherichia coli (대장균 저온 유도성 유전자 Promoter의 단백질 생산성에 관한 연구)

  • Kim, So-Yeon;Kim, Su-Hyun;Heo, Mi-Ae;Lee, Sun-Gu
    • KSBB Journal
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    • v.21 no.6 s.101
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    • pp.461-465
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    • 2006
  • We investigated the protein productivity of the promoters for genes showing prolonged induction upon cold shock in Escherichia coli. Six low temperature inducible genes (frdA, glpB, hypB, katG, nupG, ompT) were selected based on the previously reported cDNA microarray based global transcription profiling of Escherichia coli Kl2 in response to cold shock. Their promoter regions were isolated from the genomic DNA of E. coli JM109 and expression levels induced by the promoters were examined by using green fluorescence protein (GFP) as a reporter at $15^{\circ}C$ and $37^{\circ}C$. Among the six promoters, the promoter for nupG showed the highest and prolonged expression at both temperatures and the cold inducibility of nupG promoter was not observed.