• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.470-478
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• 2012

Recent genome comparisons of E. coli B and K-12 strains have indicated that the makeup of the cell envelopes in these two strains is quite different. Therefore, we analyzed and compared the envelope proteomes of E. coli BL21(DE3) and MG1655. A total of 165 protein spots, including 62 nonredundant proteins, were unambiguously identified by two-dimensional gel electrophoresis and mass spectrometry. Of these, 43 proteins were conserved between the two strains, whereas 4 and 16 strain-specific proteins were identified only in E. coli BL21(DE3) and MG1655, respectively. Additionally, 24 proteins showed more than 2-fold differences in intensities between the B and K-12 strains. The reference envelope proteome maps showed that E. coli envelope mainly contained channel proteins and lipoproteins. Interesting proteomic observations between the two strains were as follows: (i) B produced more OmpF porin with a larger pore size than K-12, indicating an increase in the membrane permeability; (ii) B produced higher amounts of lipoproteins, which facilitates the assembly of outer membrane ${\beta}$-barrel proteins; and (iii) motility- (FliC) and chemotaxis-related proteins (CheA and CheW) were detected only in K-12, which showed that E. coli B is restricted with regard to migration under unfavorable conditions. These differences may influence the permeability and integrity of the cell envelope, showing that E. coli B may be more susceptible than K-12 to certain stress conditions. Thus, these findings suggest that E. coli K-12 and its derivatives will be more favorable strains in certain biotechnological applications, such as cell surface display or membrane engineering studies.

• Journal of The Korean Astronomical Society
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• v.50 no.5
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• pp.139-149
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• 2017

The Korea Astronomy and Space Science Institute plans to develop a coronagraph in collaboration with National Aeronautics and Space Administration (NASA) and to install it on the International Space Station (ISS). The coronagraph is an externally occulted one-stage coronagraph with a field of view from 3 to 15 solar radii. The observation wavelength is approximately 400 nm, where strong Fraunhofer absorption lines from the photosphere experience thermal broadening and Doppler shift through scattering by coronal electrons. Photometric filter observations around this band enable the estimation of 2D electron temperature and electron velocity distribution in the corona. Together with a high time cadence (<12 min) of corona images used to determine the geometric and kinematic parameters of coronal mass ejections, the coronagraph will yield the spatial distribution of electron density by measuring the polarized brightness. For the purpose of technical demonstration, we intend to observe the total solar eclipse in August 2017 with the filter system and to perform a stratospheric balloon experiment in 2019 with the engineering model of the coronagraph. The coronagraph is planned to be installed on the ISS in 2021 for addressing a number of questions (e.g., coronal heating and solar wind acceleration) that are both fundamental and practically important in the physics of the solar corona and of the heliosphere.

• Journal of Microbiology
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• v.43 no.spc1
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• pp.110-117
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• 2005

Salmonella enterica serovar Typhimurium causes human gastroenteritis and a systemic typhoid-like infection in mice. A critical virulence determinant of Salmonella is the ability to invade mammalian cells. The expression of genes required for invasion is tightly regulated by environmental conditions and a variety of regulatory genes. The hilA regulator encodes an OmpR/ToxR family transcriptional regulator that activates the expression of invasion genes in response to both environmental and genetic regulatory factors. Work from several laboratories has highlighted that regulation of hilA expression is a key point for controlling expression of the invasive phenotype. A number of positive regulators of hilA expression have been identified including csrAB, sirA/barA, pstS, hilC/sirC/sprA, fis, and hilD. HilD, an AraC/XylS type transcriptional regulator, is of particular importance as a mutation in hilD results in a 14-fold decrease in chromosomal hilA::Tn5lacZY-080 expression and a 53-fold decrease in invasion of HEp-2 cells. It is believed that HilD directly regulates hilA expression as it has been shown to bind to hilA promoter sequences. In addition, our research group, and others, have identified genes (hilE, hha, pag, and lon) that negatively affect hilA transcription. HilE appears to be an important Salmonella-specific regulator that plays a critical role in inactivating hilA expression. Recent work in our lab has been directed at understanding how environmental signals that affect hilA expression may be processed through a hilE pathway to modulate expression of hilA and the invasive phenotype. The current understanding of this complex regulatory system is reviewed.

• Clinical and Experimental Vaccine Research
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• v.12 no.4
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• pp.304-312
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• 2023

Purpose: Due to the many problems with commercially available vaccines, the production of effective vaccines against brucellosis is a necessity. The aim of this study was to evaluate the immune responses caused by the chimeric protein consisting of trigger factor, Bp26, and Omp31 (TBO) along with aluminum hydroxide (AH/TBO) and selenium (Se/TBO) nanoparticles (NPs) as adjuvants in mouse model. Materials and Methods: Recombinant antigen expression was induced in Escherichia coli BL21 (DE3) bacteria using IPTG (isopropyl-d-1-thiogalactopyranoside). Purification and characterization of recombinant protein was conducted through NiFe₃O₄ NPs, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot. NP characteristics, including morphology and particle size, were measured in vitro. The recombinant TBO was loaded on to AH and Se NPs and were administered subcutaneously. After mice immunization, measurement of antibody titter and protection assay was performed. Results: The average sizes of AH and Se NPs were about 60 nm and 150 nm, respectively. The enzyme-linked immunosorbent assay results showed that the serum of mice immunized by subcutaneous injection with both nanovaccines produced significant immunoglobulin G (IgG) responses against the chimeric antigen. The results of TBO-specific IgG isotype (IgG2a/IgG1) analysis showed that both AH and Se NPs induced a type to T-helper immune response. In addition, the results of the challenge with the pathogenic strain of Brucella melitensis 16M showed that vaccinated mice with AH/TBO NPs indicated a higher reduction of bacterial culture than immunized mice with Se/TBO NPs and TBO alone. Conclusion: The results showed that AH NPs carrying chimeric antigen can be a promising vaccine candidate against brucellosis by producing protective immunity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.659-667
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• 2004

Plantain has been used for antidiarrhea, antihemorrhage and the remedy of indigestion. Plantain was extracted with ethanol and fractionated systemically with n-hexane, chloroform, ethylacetate (EtOAC) and n-butanol. Antioxidant index (AI was expressed as induction period of oil containing various fractions/induction period of oil of 600 ppm) of EtOAC fraction was the highest among fractions in vitro. The protective effects of the EtOAC fraction of plantain (PE) administered 1 mL orally or intraduodenally on experimentally induced gastritis, gastric ulcer and gastric secretion were evaluated in rats. Sprague-Dawley rats weighing 250∼300 g were divided into 4 groups; negative control group (CON), PE 200 mg/kg treated group (PEL), PE 400 mg/kg treated group (PEH) and positive control group (cimetidine 100 mg/kg-CMT or omeprazol 100 mg/kg treated group-OMT), respectively, PE significantly suppressed HCl-ethanol induced gastric lesions and indomethacin-induced gastric ulcers (administered subcutaneouly) in rats. Specially PE 400 mg/kg showed significantly inhibitory effect, which was more potent than that of 100 mg/kg of commercial drug, cimetidine, and elevated an inhibitory effect to be close to the level in inhibitory ratio of omeprazol administered group in Shay's ucler. On gastric secretion in pylorus ligated rat, PE 200 mg/kg and 400 mg/kg decreased the gastric volume and acid output, but did not show an apparent effect on pepsin activity. In addition, PE 400 mg/kg depressed gastric ulcers induced by water immersion stress and duodenal ulcers induced by cysteamine administered subcutaneouly. These results suggest that the ethylacetate fraction of plantain can be used in prevention and treatment of experimentally induced gastric mucosal damage and ulcers.

• Pediatric Infection and Vaccine
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• v.10 no.1
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• pp.71-80
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• 2003

Purpose : Four kinds of Haemophilus influenzae type b protein conjugate vaccines, PRPD, PRP-T, PRP-OMP and PRP-CRM197, have been developed, and PRP-T vaccines are currently produced by two manufacturer, $ActHib^{(R)}$ by Aventis and $Hiberix^{TM}$ by GlaxoSmith-Kline Biologicals. The purpose of this study is to evaluate the immunogenicity and safety of $Hiberix^{TM}$ in Korean infants. Methods : Seventy-three healthy infants(43 male infants) were recruited for this study after parental informed consent was obtained. Each infant was vaccinated at 2, 4 and 6 months of age with the study vaccine. At each visit, infants were also immunized with DTaP, trivalent oral polio vaccine and hepatitis B vaccine when indicated. The serum anti-PRP antibody was measured at prevaccination, 2 month later after the 2nd dose, and 1 month later after the 3rd dose by the ELISA method. The local and systemic adverse reactions of vaccination were monitored for 3 consecutive days after each immunization. Immunogenicity of vaccine was evaluated in infants who received all the scheduled immunization and the adverse reactions were evaluated for infants who received at least one dose of the study vaccine. Results : Among seventy three infants, enrolled in this study; sixty three(37 male infants) completed all the scheduled immunizations. The geometric mean titer(GMT) of anti-PRP antibodies at prevaccination was 0.17 ${\mu}g/mL$(95% confidence interval[CI]; 0.13~0.22). The GMT of anti-PRP antibodies increased to 4.14 ${\mu}g/mL$(95% CI; 2.65~6.48) at 2 month later after the 2nd dose of PRP-T and 14.65 ${\mu}g/mL$(95% CI; 10.83~19.81) at 1 month later after the 3rd dose. Anti-PRP antibody ${\geq}0.15$ ${\mu}g/mL$, was observed in 98.4%(95% CI; 91.8~100) after 2 doses and 100%(95% CI; 100~100) after 3 doses. Anti-PRP antibody ${\geq}1.0$ ${\mu}g/mL$, was obtained in 77.8%(95% CI; 67.5~88.0) after 2 doses, and 98.4%(95% CI; 95.3~100) after 3 doses. Most of the adverse reaction after vaccination were mild. Irritability, the most common systemic reaction, was observed in 45.5%, followed by drowsiness(30.5%), poor feeding(26.7%) and fever(5.6%). Among the local reactions tenderness was observed in 7.9%, redness(${\geq}5$ mm) in 2.8% and swelling(${\geq}5$ mm) in 1.8%. Conclusion : The PRP-T vaccine used in this study was highly immunogenic and safe in Korean young infants. The finding that high GMT and high frequency of infants with a protective titer achieved after 2 doses is consistent with the previous studies which were done with a PRP-T vaccine of other manufacturer. This study suggests that the immunization schedule of PRP-T vaccine for Korean infants may need re-evaluation.

• Journal of fish pathology
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• v.19 no.1
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• pp.45-54
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• 2006

The immunogenicity of Edwardsiella tarda was surveyed under two different culture conditions. In SDS-PAGE patterns of the outer membrane proteins (OMPs) extracts of E. tarda, grown under Trypic soy broth (TSB) and TSB supplemented iron chelate 2,2‘-dipyridyl iron-restricted condition, were examined. The results showed that the iron-regulated outer membrane protein (IROMPs) with molecular masses of 68 and 73 kDa were expressed by bacteria grown in iron-chelate TSB.The pathogenicity was examined by intraperitoneal injection with live E. tarda grown under TSB, iron-chelate TSB and iron-supplemented TSB. The result of pathogenicity test showed significantly high mortality in the group of live E. tarda grown under iron-chelate TSB.The effect of formalin killed cell (FKC) of TSB cultured bacteria and 2,2'-dipyridyl FKC (DP-FKC) of cultured bacteria on the iron-chelate TSB on the development of protective immunity in olive flounder was studied. The level of immune response was evaluated with immunized fish at 1, 2, 3 and 4 weeks after immunization. The numbers of specific antibody secreting cells (SASCs) showed significantly increased level at 2 week after immunization in each group. The agglutination titre of immunized fish was significantly high level at 3 weeks after immunization.The level of protection in olive flounder at 1, 2, 3 and 4 weeks after vaccination was examined by intraperitoneal challenge test with live E. tarda.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1545-1552
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• 2005

Sanguisorba officinalis L. has been used as a traditional remedy for arthritis, neuralgia, diarrhea, vomiting, gastric ulcer and gastro-intestinal disorders. This study was performed to investigate the protective effects of ethylacetate fraction of Sanguisorba officinalis L. ethanol extract (SOE) on the gastric mucosal damage and gastric ulcer induced by HCI-ethanol, indomethacin, Shay-ligation method, restraint and water-immersion stress, and cysteamine in rats. The experiment animals were divided into four groups: a negative control group (CON), positive control group (cimetidine 100 mg/kg-CMT or omeprazol 100 mg/kg administrated group-OMT), SOE 200 mg/kg administrated group (SOL) and SOE 400 mg/kg administrated group (SOH), respectively. Rats were given an oral or intraduodenal administration of SOE, and all SOE treatment groups compared with the CON significantly inhibited HCI-ethanol-induced acute gastritis and indomethacin-induced gastric ulcers in dose-dependent manner, of which effects were lower in a positive control drug (CMT). The inhibition rates ($\%$) on the acute gastritis induced by HCI-ethanol and the gastric ulcers induced by indomethacin in rats, 17.66$\%$ and 48.28$\%$ in SOL, 21.71$\%$, and 51.08$\%$ in SOH, and 47.26$\%$ and 58.26$\%$ in CMT compared with CON, respectively, In pylorus ligated rats, the groups of SOE showed decreases in the volume of gastric secretion and acid output. However, no significant differences were observed in the pepsin activity between treated groups . In addition, SOH also depressed gastric ulcers induced by restraint and water-immersion stress and duodenal ulcers induced by cysteamine. These results suggest that Sanguisorba officinalis L. has remarkable antigastric ulcer effects and could be developed as a new antigastric ulcer agents.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.38.2-39
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• 2021

I will presents the analysis of the gas properties of the protoplanetary disk surrounding the young low-mass (about 1.2M_sun) triple star, GG Tau A. This work makes use of ALMA observations of rotational lines of CO (¹²CO, ¹³CO and C¹⁸O) together NOEMA observations of a few dozens of other molecules. While the CO emission gives information on the molecular layer close to the disk atmosphere, its less abundant isotopologues ¹³CO and C¹⁸O bring information much deeper in the molecular layer. I will present the analysis of the morphology and kinematics of the gas disk using the CO isotopologues. A radiative transfer model of the ring in CO isotopologues will also be presented. The subtraction of this model from the original data reveals the weak emission of the molecular gas lying inside the cavity. Thus, I am able to evaluate the properties of the gas inside the cavity, such as the gas dynamics, excitation conditions, and the amount of mass in the cavity. High angular resolution observations of CO reveals sprials induced by embedded planet(s) located near the 3:2:1 mean-motion resonance that help to explain the special morphology of the circumbinary disk. I also discuss some chemical properties of the GG Tau A disk. I report the first detection of H2S and C₂S in a protoplanetary disk. The molecule abundance relative to ¹³CO of about twenties other molecules will also be given. In GG Tau A, the detections of rare molecules such as H₂S and C₂S have been probably possible because the disk is more massive (a factor about 3-5) than other disks where the molecules was searched. Such a large disk mass makes the system suitable to detect rare molecules and to study cold-chemistry in protoplanetary disks.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.11a
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• pp.131-186
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• 2002

우리나라 유통상토에 대한 물리적 표준분석법을 설정하기 위한 연구를 실시하였다. 국내 시중에 유통되고 있는 53개 품목의 원예용 상토와 9개 품목의 수도용 상토를 대상으로 설정된 분석법을 적용하여 실험하였다. 입자밀도의 측정은 가스형 피크노메타(Micromeritics Co. Model 1305)를 사용하면 속도와 정확성 면에서 매우 유리하였다. 용적밀도는 구미에서 Sandbox법에 의한 용적밀도를 기본으로 하기 때문에 이와 유사한 성적을 얻을 수 있는 다양한 실험을 한 결과, 추다짐법(Plunger compaction method)이 가장 유의성 있는 측정 방법으로 밝혀졌다. 한편 가스형 피크노메타법에 의한 우리나라 유통상토의 입자밀도는 원예용이 1.93, 수도용이 2.43 Mg m$^{-3}$로 나타났으며, 추다짐법에 의한 용적밀도는 원예용이 0.22, 수도용이 1.01 Mg m$^{-3}$로 각각 나타났다. 수분함량은 105$^{\circ}C$ 건조기에서 16시간 건조하여 수도용상토는 (최초 무게-건조 후 무게) / (건조 후 무게) $\times$ 100으로, 원예용상토는 (최초무게 - 건조 후 무게) / (최초 무게) $\times$ 100으로 하였다. 보수력은 주로 저압용으로서 Eijkelkamp사의 Sandbox법을 사용하여 0.5, 1, 3, 5, 7, 10 ㎪의 수분장력 상태의 수분함량을 조사하였다. 포화수리전도도는 직경 5cm$\times$높이 20cm인 아크릴 원통을 이용하여 정수위별에 의한 포화수리전도도를 측정하였다. 신분석법에 의한 유통상토의 수분함량은 원예용이 평균 46.34%, 수도용이 평균 16.89%이었고 원예용 상토의 EAW는 28.4%, WBC 7.01%, OMP는 5.60 ㎪로 나타났으며, 육묘를 위한 적정 수분함량은 44.41%이었고 포화수리전도도는 1.71 cm $min^{-1}$이었다. 상토 평량시 무게를 비교한 결과 상토 부피를 달리하여도 고도의 유의성이 있었고, 상토 20cc의 평균무게는 4.92g(2.08-8.83g)이었다. 상토의 EC 측정시 상토:물의 비율이 1:2(v:v)와 1:5(v:v)분석치에 2.5배한 EC 값과는 고도의 정의 상관관계가 있었으며, 유럽법과 일본법(전농)과의 관계는 고도의 정의 상관관계가 있었다 또한 새로운 분석법(v:v 1:5)으로 측정한 EC의 평균값은 국내산 0.64, 수입산 0.33 dS m$^{-1}$이 었다. 상토의 pH 측정시 상토:물의 비율을 1:2(v:v)와 1:5(v:v)와의 관계에서는 정의 상관관계를 보였으며, 유럽법과 일본법(전농)과의 관계도 역시 고도의 정의 상관관계가 있었고, 신 분석법에(v:v 1:5) 의한 분포비율은 국내산, 수입산모두 pH 6.1-6.5의 범위에서 가장 높았다.