• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.604-610
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• 2007

A psychrotrophic strain 7195 showing extracellular lipolytic activity towards tributyrin was isolated from deep-sea sediment of Prydz Bay and identified as a Psychrobacter species. By screening a genomic DNA library of Psychrobacter sp. 7195, an open reading frame of 954 bp coding for a lipase gene, lipA1, was identified, cloned, and sequenced. The deduced LipA1 consisted of 317 amino acids with a molecular mass of 35,210 kDa. It had one consensus motif, G-N-S-M-G (GXSXG), containing the putative active-site serine, which was conserved in other cold-adapted lipolytic enzymes. The recombinant LipA1 was purified by column chromatography with DEAE Sepharose CL-4B, and Sephadex G-75, and preparative polyacrylamide gel electrophoresis, in sequence. The purified enzyme showed highest activity at $30^{\circ}C$, and was unstable at temperatures higher than $30^{\circ}C$, indicating that it was a typical cold-adapted enzyme. The optimal pH for activity was 9.0, and the enzyme was stable between pH 7.0-10.0 after 24h incubation at $4^{\circ}C$. The addition of $Ca^{2+}\;and\;Mg^{2+}$ enhanced the enzyme activity of LipA1, whereas the $Cd^{2+},\;Zn^{2+},\;CO^{2+},\;Fe^{3+},\;Hg^{2+},\;Fe^{2+},\;Rb^{2+}$, and EDTA strongly inhibited the activity. The LipA1 was activated by various detergents, such as Triton X-100, Tween 80, Tween 40, Span 60, Span 40, CHAPS, and SDS, and showed better resistance towards them. Substrate specificity analysis showed that there was a preference for trimyristin and p-nitrophenyl myristate $(C_{14}\;acyl\; groups)$.

• 한국지역지리학회지
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• 제3권2호
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• pp.89-103
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• 1997

국제적인 관광 지리학의 발달에 따르면, 미국의 경우 1920년대로 거슬로 올라가며 미국내 지리저널에서 관광을 주재로 언급했던 최초의 논문은 1933년에 발표된 바 있고, 영국과 프랑스 그리고 일본은 1930년대 출판된다. 한편, 국내에서는 이보다 다소 늦은 1960년대 들어서 비로소 관광 지리 연구가 시작되며 그 이후 커다란 변화를 맞이하고 있는 실정이다. 본 연구는 그간의 국내 관광지리학의 연구 성과에 대한 유형별 정량적 고찰을 동해 앞으로의 관광 지리학 연구 활동에 기초 자료로 보탬이 되고자 한다. 연구방법으로는 우선 주제의 대상을 동해 일차적 분류작업을 거쳤으며, 다음으로 세부적인 소 주제 내용을 설정하였고, 그 결과 전체 7개의 영역을 구분지었다. 주된 연구 결과에 따르면, 특정 주제 중심의 연구 활동에서 좀더 폭 넓은 내용을 주제로 한 연구 활동이 있어야 할 것이며 또한, 관광 지리학의 기초 이론 연구에 대한 작업이 강화되어야 할 것으로 본다.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.474-481
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• 1996

Since the commercially available rabbit anti-cyclin D3, generated from c-terminal 16 amino acid residues which are common to human and murine cyclin D3, is highly cross-reactive with many other cellular proteins of mouse, a new rabbit polyclonal anti-cyclin D3 has been raised by using murine cyclin D3 protein expressed at a high level in Escherichia coli as the immunogen. To express murine cyclin D3 protein in E. coli, the cyclin D3 cDNA fragment encoding c-terminal 236 amino acid residues obtained by polymerase chain reaction (PCR) was inserted into the NcoI/BamHI site of protein expression vector, pET 3d. Molecular mass of the cyclin D3 overexpressed in the presence of IPTG (Isopropyl $\beta$-D-thiogalactopyranoside) was approximately 26 kDa as calculated from the reading frame on the DNA sequence, and the protein was insoluble and mainly localized in the inclusion bodies that could be easily purified from the other cellular soluble proteins. When renaturation was performed following denaturation of the insoluble cyclin D3 protein in the inclusion bodies using guanidine hydrochloride, 4.4 mg of soluble form of cyclin D3 protein was produced from the transformant cultured in 100ml of LB media under the optimum conditions. Four-hundred micrograms of the soluble form of cyclin D3 protein was used for each immunization of a rabbit. When the antiserum obtained 2 weeks after tertiary immunization was applied to Western blot analysis, it was able to detect 33 kDa cyclin D3 protein in both murine lymphoma cell line BW5147.G.1.4 and human Jurkat T cells at 3,000-fold dilution with higher specificity to murine cyclin D3, demonstrating that the new rabbit polyclonal anti-murine cyclin D3 generated against c-terminal 236 amino acid residues more specifically recognizes murine cyclin D3 protein than does the commercially available rabbit polyclonal antibody raised against c-terminal 16 amino acids residues.

• Journal of Microbiology and Biotechnology
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• 제26권11호
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• pp.1855-1862
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• 2016

Cronobacter sakazakii (C. sakazakii) is a foodborne pathogen, posing a high risk of disease to infants and immunocompromised individuals. In order to develop a quick, easy, and sensitive assay for detecting C. sakazakii, a rabbit anti-C. sakazakii immunoglobulin G (IgG) was developed using sonicated cell protein from C. sakazakii. The developed anti-C. sakazakii (IgG) was of good quality and purity, as well as species-specific. The developed rabbit anti-C. sakazakii IgG was attached to the surface of a sulforhodamine B-encapsulated liposome to form an immunoliposome. A test strip was then prepared by coating goat anti-rabbit IgG onto the control line and rabbit anti-C. sakazakii IgG onto the test line, respectively, of a plastic-backed nitrocellulose membrane. A purple color signal both on the test line and the control line indicated the presence of C. sakazakii in the sample, whereas purple color only on the control line indicated the absence of C. sakazakii in the sample. This immunochromatographic strip assay could produce results in 15 min with a limit of detection of $10^7CFU/ml$ in C. sakazakii culture. The immunochromatographic strip assay also showed very good specificity without cross-reactivity with other tested Cronobacter species. Based on these results, the developed immunochromatographic strip assay is efficient for the detection of C. sakazakii and has high potential for on-site detection.

• BMB Reports
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• 제35권2호
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• pp.206-212
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• 2002

The NS2B-NS3(pro) polyprotein segment from the dengue virus serotype 2 strain 16681 was purified from overexpressing E. coli by metal chelate affinity chromatography and gel filtration. Enzymatic activity of the refolded NS2B-NS3(pro) protease complex was determined in vitro with dansyl-labeled peptide substrates, based upon native dengue virus type 2 cleavage sites. The 12mer substrate peptides and the cleavage products could be separated by reversed-phase HPLC, and were identified by UV and fluorescence detection. All of the peptide substrates (representing the DEN polyprotein junction sequences at the NS2A/NS2B, NS2B/NS3, NS3/NS4A and NS4B/NS5 sites) were cleaved by the recombinant protease NS2B-NS3(pro). No cleavage was observed with an enzymatically inactive S135A mutant of the NS3 protein, or with a modified substrate peptide of the NS3/NS4A polyprotein site that contained a K2093A substitution. Enzymatic activity was dependent on the salt concentration. A 50% decrease of activity was observed in the presence of 0.1M sodium chloride. Our results show that the NS3 protease activity of the refolded NS2B-NS3(pro) protein can be assayed in vitro with high specificity by using cleavage-junction derived peptide substrates.

• BMB Reports
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• 제29권6호
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• pp.519-524
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• 1996

Peptidylprolyl cis-trans isomerase (PPlase) catalyzes the cis-trans isomerization of prolyl peptide and facilitates the folding of cellular proteins and peptides. PPlase consists of two distinct immunophilins, each specifically binding to the immunosupressive drug cyclosporin A (CsA) or FK506, respectively. A PPlase was isolated and partially purified from porcine spleen. The molecular weight of porcine spleen PPlase was determined to be ~14,000 on the basis of SDS-PAGE. The purified enzyme was strongly inhibited by FK506, but not by CsA. The inhibition constant and the true concentration of enzyme preparations were determined by active site titration using the tight binding inhibitor FK506: $K_{i}=18.7$ nM and $E_{t}=172$ nM. The equilibrium ratio of conformer. [cis]/[trans], of prolyl peptide substrates (N-Suc-Ala-Xaa-Pro-Phe-p-NA) in anhydrous trifluoroethanol/LiCl solvent system varied from 0.24 to 0.85 depending on the nature of Xaa. Overall. in this solvent-salt system, the populations of the cis conformer of substrates in equilibrium are higher than in an aqueous solution so that the substantial error caused by high background absorption can be reduced. The reactivities of porcine spleen PPlase are shown to be highly sensitive to changes in the structure of substrates. Thus, $k_{cat}/K_m$ value for the most reactive substrate (Xaa Leu) is $4.007+10^{6}M^{1}s^{1}$ and, is 2,636 fold higher than that for the least reactive peptide substrate tested, Xaa=Glu.

• Tuberculosis and Respiratory Diseases
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• 제38권1호
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• pp.45-52
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• 1991

Clinical analysis was performed on 306 patients with cervical lymphadenopathy who were diagnosed histologically by fine needle aspiration biopsy cytology (FNABC) and/or excisional biopsy from Jan 1986 to Jan 1990 at Hanyang University hospital. The results obtained were as follows: 1) Of 306 patients with cervical lymphadenopathy, 216 (70.6%) were inflammatory lesions, and 90 (29.4%) malignant lesions. Tuberculous lymphadenitis of inflammatory lesions was most common (134 cass: 62%). Of malignant lesions, metastatic cancer was more frequent (75 cases: 83.3%). 2) The sex ratio were as follows: inflammatory lesion; M:F=1 : 1.8 (tuberculous lymphadenitis;M : F=1:2.3) malignant lesion; M : F=1.5 : 1 (metastatic cancer; M : F=2.6 : 1) 3) The peak age of inflammatory lymphadenopathy was 20-29 years old (38.9%), and that of malignant lesion 50-59 years old (46.7%). 4) In more than half of tuberculous lymphadenitis and metastatic cancer, the location of enlarged lymph nodes was one side of the neck and the number was more than one. 5) The common primary sites of metastatic cancer were lung and stomach. In 11 cases (14.7%), the primary site could not be found. 6) The sensitivity and the specificity of fine needle aspiration biopsy cytology (FNABC) was 0.83 & 1.0 in metastatic cancer respectively.

• Journal of Ginseng Research
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• 제41권3호
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• pp.326-329
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• 2017

Background: Cultivated ginseng is often introduced as a substitute and adulterant of Russian wild ginseng due to its lower cost or misidentification caused by similarity in appearance with wild ginseng. The aim of this study is to develop a simple and reliable method to differentiate Russian wild ginseng from cultivated ginseng. Methods: The mitochondrial NADH dehydrogenase subunit 7 (nad7) intron 3 regions of Russian wild ginseng and Chinese cultivated ginseng were analyzed. Based on the multiple sequence alignment result, a specific primer for Russian wild ginseng was designed by introducing additional mismatch and allele-specific polymerase chain reaction (PCR) was performed for identification of wild ginseng. Real-time allele-specific PCR with endpoint analysis was used for validation of the developed Russian wild ginseng single nucleotide polymorphism (SNP) marker. Results: An SNP site specific to Russian wild ginseng was exploited by multiple alignments of mitochondrial nad7 intron 3 regions of different ginseng samples. With the SNP-based specific primer, Russian wild ginseng was successfully discriminated from Chinese and Korean cultivated ginseng samples by allele-specific PCR. The reliability and specificity of the SNP marker was validated by checking 20 individuals of Russian wild ginseng samples with real-time allele-specific PCR assay. Conclusion: An effective DNA method for molecular discrimination of Russian wild ginseng from Chinese and Korean cultivated ginseng was developed. The established real-time allele-specific PCR was simple and reliable, and the present method should be a crucial complement of chemical analysis for authentication of Russian wild ginseng.

• 미생물학회지
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• 제32권4호
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• pp.301-305
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• 1994

토양분리 방선균 Streptomyces diastatochromogenes로부터 분리된 제한효소 SdiI은 넓은 범위의 pH(7.0~12.5)와 온도 ($-60^{\circ}C$)에서 활성을 보였으며, 고농도 (-500mM) NaCl이 있어도 작용하였다. 또한, $20~60^{\circ}C$ 온도에서 안정하며, 활성을 갖기 위해서는 $MgCl_2$를 필요로 하였다. Lambda DNA에 대한 지도 작성으로부터 XhoI의 isoschizomer로 추정되었으며, DNa 염기서열 분석 결과, 인식, 절단 서열은 다음과 같이 결정되었다. 5‘-C${\downarrow}$TCGA G-3' 3'-G AGCT${\uparrow}$C-5'

• 한국가스학회지
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• 제22권1호
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• pp.78-85
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• 2018

본 연구를 통하여 반도체 FPD 제조설비 및 클린룸에 관련한 설비의 위험성분석과 그에 대한 근원적인 안전대책을 연구하고, 설비 및 환경의 특수성을 고려한 방폭 설계 모델링화를 검토하여 관련 설비의 설계 및 제작에 기술적인 기준과 근거로 활용하고자 하며, 아래와 같은 성과로서 향후 반도체 FPD 산업의 기술적 기준 수립 및 관련 산업에 기여할 것으로 생각한다. 1) 관련 국제 기술규격과 법령, 설비의 특성을 반영한 FAB 장비의 최적화된 폭발위험장소의 모델링 도출 2) FAB 장비 및 클린 룸의 특성을 고려한 위험설비의 안전성 확보 (Fool-Proof와 Fail Safe)를 위한 안전시스템 구축방안과 안전기준 및 대책 도출 3) 향후 FAB 장비의 방폭 설계에 대한 가장 효율적인 기준 적용을 통한 신규 FAB 장비의 방폭 성능의 유연성 확보하고 수립된 안전기준을 통한 설비와 안전시스템의 신뢰성 검증 절차 운영을 위한 "안전인증제도"의 자율적 향상화.