• Molecules and Cells
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• 제26권2호
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• pp.140-145
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• 2008

Expression of olive flounder hepcidin I (HepI) fused with truncated OmpA signal peptides ($OmpASP_{tr}$) as directional signals does not produce soluble fusion proteins. However, by inserting amino acid segments (xxx) varying in pI and hydrophobicity/hydrophilicity into a leader sequence containing a truncated OmpASP ($OmpASP_{tr}$) and a factor Xa cleavage site (Xa) [$OmpASP_{tr}{\mid}(xxx){\mid}Xa$], we were able in some cases to express soluble recombinant HepI. Soluble expression of the recombinant protein strongly correlated with (xxx) insertions of high pI and hydrophilicity. Therefore, we modified the $OmpASP_{tr}{\mid}(xxx){\mid}Xa$ sequence by inserting Arg and Lys into (xxx) to increase the hydrophilicity of the signal peptide region. These modifications enhanced the expression of soluble recombinant HepI. Hydropathic profile analysis of the $OmpASP_{tr}{\mid}(xxx){\mid}Xa$ HepI fusion proteins revealed that the transmembrane-like domains derived from the $OmpASP_{tr}{\mid}(xxx){\mid}Xa$ sequence were larger than the internal positively charged domain native to HepI. It should therefore be possible to overcome the obstacle of internal positively charged domains to obtain soluble expression of recombinant proteins by monitoring the hydrophilicity and hydropathic profile of the signal peptide region using a computer program.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.854-861
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• 2014

The diagnosis of Brucella abortus is mainly based on serological methods using antibody against LPS, which has diagnostic problems. Therefore, to solve this problem, we evaluated two proteins of B. abortus, Cu/Zn superoxide dismutase (SodC) and outer membrane proteins 2b porin (Omp2b). The genes were cloned and expressed in a pMAL system, and the recombinant proteins, rOmp2b and rSodC, were purified as fusion forms with maltose-binding protein. The identity of the proteins was confirmed by SDS-PAGE and Western blot analysis with sera of mice infected with B. abortus. Production of cytokines and nitric oxide (NO) was investigated in RAW 264.7 cells and mouse splenocytes after stimulation with the proteins. Moreover, cellular and humoral immune responses were investigated in BALB/c mice after immunization with the proteins. TNF-${\alpha}$, IL-6, and NO were significantly inducible in RAW 264.7 cells. Splenocytes of naive mice produced IFN-${\gamma}$ and IL-4 significantly by stimulation. Moreover, number of IgG, IFN-${\gamma}$, and IL-4 producing cells were increased in immunized mice with the two proteins. Production of IgG and IgM with rOmp2b was higher than those with rSodC in immunized mice. These results suggest that the two recombinant proteins of B. abortus may be potential LPS-free proteins for diagnosis.

• Journal of Veterinary Science
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• 제19권6호
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• pp.808-816
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• 2018

Bacterial biofilms have been demonstrated to be closely related to clinical infections and contribute to drug resistance. Berberine, which is the main component of Coptis chinensis, has been reported to have efficient antibacterial activity. This study aimed to investigate the potential effect of a combination of berberine with ciprofloxacin (CIP) to inhibit Salmonella biofilm formation and its effect on expressions of related genes (rpoE, luxS, and ompR). The fractional inhibitory concentration (FIC) index of the combination of berberine with CIP is 0.75 showing a synergistic antibacterial effect. The biofilm's adhesion rate and growth curve showed that the multi-resistant Salmonella strain had the potential to form a biofilm relative to that of strain CVCC528, and the antibiofilm effects were in a dose-dependent manner. Biofilm microstructures were rarely observed at $1/2{\times}MIC/FIC$ concentrations (MIC, minimal inhibition concentration), and the combination had a stronger antibiofilm effect than each of the antimicrobial agents used alone at $1/4{\times}FIC$ concentration. LuxS, rpoE, and ompR mRNA expressions were significantly repressed (p< 0.01) at $1/2{\times}MIC/FIC$ concentrations, and the berberine and CIP combination repressed mRNA expressions more strongly at the $1/4{\times}FIC$ concentration. The results indicate that the combination of berberine and CIP has a synergistic effect and is effective in inhibiting Salmonella biofilm formation via repression of luxS, rpoE, and ompR mRNA expressions.

• 대한수의학회지
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• 제32권2호
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• pp.181-194
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• 1992

Two hundred and eighty nine strains of Yersinia enterocolitica isolated from healthy pigs were tested for the presence of 40~50 Megadalton virulence-associated plasmids and plasmidmediated in vitro virulence-associated properties, i.e., congo red uptake, calcium dependency, autoagglutination, CRMOX reaction, crystal violet binding and pyrazinamidase reaction. The correlationships between in vitro virulence-associated properties and the presence of 220 Kdalton outer membrane protein(OMP) were examined in strains with or without virulence-associated plasmids. The correlationships between the presence of plasmids on the production of the OMP and the expression of in vitro virulence-associated properties were studied with $CRMOX^+$ strains and acridine orangecured $CRMOX^-$ mutants. The results were as follows : 1. Of the in vitro virulence-associated tests with 289 strains of Y enterocolitica, 275 strains (95.2%) were positive for pyrazinamidase test, and followed by in order of crystal violet binding test, 226 (79.2% ) ; CRMOX test, 190 (65.7%) ; autoagglutination test, 1.85(64.0%) : calcium dependency test, 86 (29.8%) and congo red uptake test, 47(16.3%). 2. The correlationship between autoagglutination and CRMOX test(r=0.90) was highly significant (p<0.01). 3. In 190 strains(65.7%) bearing the virulence-associated plasmids(MW 40~50 Mdalton), the correlation between the presence of plasmids and their in vitro virulence-associated properties were highest with CRMOX test(r=0.93) and followed by in orders of AAG test(0.81), CV test(0.46), PYZ test(0.37) and CD test(0.18), but no correlationship between the presence of plasmids and CR test(-0.11). 4. The $CRMOX^+$ strains produced the 220 Kdalton OMP when they were cultured at $37^{\circ}C$, but not at $26^{\circ}C$. The presence of 220 Kdalton OMP was correlated significantly with in vitro virulence properties and the presence of virulence-associated plasmid, respectively. 5. In the isogenic $CRMOX^-$ mutant strains, of which plasmid were cured by treatment with acridine orange not only in vitro virulence-associated properties(CR 100%, CD 100%, AAG 82.6%, CV 58.3%) disappeared but also 220 Kdalton OMP(100%) was not produced. These results indicate that the positive CRMOX reaction is plasmid-mediated and the CRMOX test is potential as an in vitro virulence tests with Y enterocolitica.

• Journal of Microbiology and Biotechnology
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• 제30권4호
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• pp.497-504
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• 2020

For control of brucellosis in small ruminants, attenuated B. melitensis Rev1 is used but it can be virulent for animals and human. Based on these aspects, it is essential to identify potential immunogens to avoid these problems in prevention of brucellosis. The majority of OMPs in the Omp25/31 family have been studied because these proteins are relevant in maintaining the integrity of the outer membrane but their implication in the virulence of the different species of this genus is not clearly described. Therefore, in this work we studied the role of Omp31 on virulence by determining the residual virulence and detecting lesions in spleen and testis of mice inoculated with the B. melitensis LVM31 mutant strain. In addition, we evaluated the conferred protection in mice immunized with the mutant strain against the challenge with the B. melitensis Bm133 virulent strain. Our results showed that the mutation of omp31 caused a decrease in splenic colonization without generating apparent lesions or histopathological changes apparent in both organs in comparison with the control strains and that the mutant strain conferred similar protection as the B. melitensis Rev1 vaccine strain against the challenge with B. melitensis Bm133 virulent strain. These results allow us to conclude that Omp31 plays an important role on the virulence of B. melitensis in the murine model, and due to the attenuation shown by the strain, it could be considered a vaccine candidate for the prevention of goat brucellosis.

• 미생물학회지
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• 제48권3호
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• pp.187-191
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• 2012

Two component system (TCS)인 ZraS/R 및 CusS/R의 zraP와 cusC 유전자의 프로모터에 의해 green fluorescent protein (GFP)이 발현되도록 제작된 박테리아 바이오센서의 성능을 인공폐수에서 평가하였다. 제작된 박테리아 바이오센서는 실제 폐수를 모사한 인공폐수에서도 시료 중의 $Zn^{2+}$와 $Cu^{2+}$를 인지하여 GFP를 효율적으로 발현시키는 것을 확인할 수 있었다. 두 번째는 세포 표면에 금속 친화성 펩타이드가 표현되도록 제작된 구리 및 아연 제거 박테리아를 인공폐수 조건에서 평가하였다. 제작된 박테리아는 각각 ZraS/R 및 CusS/R TCS에 의해 주변의 $Zn^{2+}$와 $Cu^{2+}$를 인지하여 세포 표면에 OmpC-ZBP와 OmpC-CBP 융합 단백질을 발현시키는 시스템이다. 실험을 통해 표면에 금속 흡착 펩타이드가 발현된 재조합 균은 인공폐수 조건에서도 효과적으로 구리 및 아연을 흡착시키는 것을 확인하였다. 따라서 본 연구에서 개발된 TCS 기반 재조합 균은 인공폐수 조건에서 중금속의 인지 및 제거 기능이 효과적으로 작동하는 것이 확인되었다.

• 생명과학회지
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• 제14권6호
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• pp.986-990
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• 2004

2002년 5월에서 7월사이 한국 근해로부터 총 가검물 50례 중에서 V. vulnificus은 5균주가 분리되었고, API 20E kit의동정률이 $89.4\~93.7\%$로 나타났다. V. vulnificus 16S rDNA를 증폭하여 얻은 산물을 cloning하여 염기서열을 결정하고 분석한 결과 V. vulnificus로 확인되었다. 동정된 분리균주들의 cell lysates을 SDS-PAGE로 분석하였고 표준균주로 사용된 V. vulnificus ATCC 27562와 분리 균주들을 비교해 본 결과 단백밴드pattern이 많은 차이를 보였으나 외막단백질은 V. vulnificus간에는 공통의 밴드가 확인되었으나 V. parahaemolyticus 와는 차이를 보였다.

• 한국동물위생학회지
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• 제32권4호
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• pp.335-341
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• 2009

Canine brucellosis produce abortions and infertility in dogs and is currently diagnosed by serological methods such as rapid slide agglutination test with 2-mercaptoethanol (2-ME RSAT) and immunochromatographic assay (ICA). Bacterial isolation is considered gold standard for Brucella diagnosis and the polymerase chain reaction (PCR) is an alternative method to bacterial isolation. A total of 36 whole blood samples were collected from dogs reared in area of Chuncheon and were subjected to serology (2-ME RSAT and ICA for B. canis, Rose Bengal test and C-ELISA for B. abortus), blood culture and 3 types of PCRs (BSCP31, 16s rRNA, and OMP-2). All blood samples were negative by serology and blood cultures. The BCSP31 and the OMP-2 PCR detected 5 samples were positive whereas the 16S rRNA PCR detected all samples were negative as serological methods and blood culture did. From the results observed in the present study, we conclude that 16S rRNA PCR could be used for direct PCR for canine blood samples.

• 한국군사과학기술학회지
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• 제21권4호
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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.

• 천문학논총
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• 제27권4호
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• pp.195-200
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• 2012

We show how the rotation emission from isolated interstellar Polycyclic Aromatic Hydrocarbons (PAHs) can explain the so-called anomalous microwave emission (AME). AME has been discovered in the last decade as microwave interstellar emission (10 to 70 GHz) that is in excess compared to the classical emission processes: thermal dust, free-free and synchrotron. The PAHs are the interstellar planar nano-carbons responsible for the near infrared emission bands in the 3 to 15 micron range. Theoretical studies show that under the physical conditions of the interstellar medium (radiation and density) the PAHs adopt supra-thermal rotation velocities, and consequently they are responsible for emission in the microwave range. The first results from the PLANCK mission unexpectedly showed that the AME is not only emitted by specific galactic interstellar clouds, but it is present throughout the galactic plane, and is particularly strong in the cold molecular gas. The comparison of theory and observations shows that the measured emission is fully consistent with rotation emission from interstellar PAHs. We draw the main lines of our PLANCK-AKARI collaborative program which intends to progress on this question by direct comparison of the near infrared (AKARI) and microwave (PLANCK) emissions of the galactic plane.