Purification and Characterization of Helicobacter pylori ${\gamma}$-Glutamyltranspeptidase

Song, Jae-Young,Choi, Yeo-Jeong,Kim, Jeong-Min,Kim, Yoo-Ree,Jo, Jin-Seong,Park, Jin-Sik,Park, Hee-Jin,Song, Yun-Gyu,Lee, Kon-Ho,Kang, Hyung-Lyun,Baik, Seung-Chul,Youn, Hee-Shang,Cho, Myung-Je,Rhee, Kw The Korean Society for Microbiology 2011 Journal of Bacteriology and Virology Vol.41 No.4

Gamma-glutamyltranspeptidase (GGT) was purified to electrophoretic homogeneity from the cell extract of H. pylori. The purified enzyme consisted of heavy and light subunits with molecular weights of 38 kDa and 21 kDa, respectively. N-terminal amino acid sequence of heavy and light subunits revealed that H. pylori GGT was processed into 3 parts for a signal peptide of 27 amino acid residues, a heavy subunit of 352 residues, and a light subunit of 188 residues during translation. The reaction rate for hydrolysis of ${\gamma}$-GpNA was 84.4 ${\mu}mol/min$ per milligram of protein, and that for the ${\gamma}$-glutamyl transfer from ${\gamma}$-GpNA to gly-gly was 23.8 ${\mu}mol/min$ per milligram of protein. The apparent Km values of H. pylori GGT for ${\gamma}$-glutamyl compounds were on the order of $10^{-3}$ to $10^{-4}$ M and those for acceptor peptides and amino acids were on the order of $10^{-1}$ to $10^{-2}$ M. The GGT protein kept approximately 80% of the initial enzymatic activity on incubation at $60^{\circ}C$ for 15 min. The optimum temperature and pH for reactions of both hydrolysis and transpeptidation were $40^{\circ}C$ and 9.0, respectively. The transpeptidation and hydrolysis reactions catalyzed by H. pylori GGT were strongly inhibited by L-Gln and moderately inhibited by L-Ala, L-Ser, ${\beta}$-chloro-L-Ala, and L-Glu. These results demonstrated that the biochemical properties of H. pylori GGT are different from those of other bacterial GGTs. Further, H. pylori GGT might degrade glutathione in the gastric mucous layer of humans if the enzyme could be secreted in the bacterial niches.

신경망을 이용한 리니어모터 이송시스템 제어

유송민 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

High speed linear motor feed system has been simulated using neural network technique. Due to the limited resources, control gain tuning has been the most troublesome part in controller design. Regardless of the system structure, conventional control gain could be adjusted minimizing the resulting error using the proposed method. Slight performance deterioration was observed at the small value of training epoch.

쥐 뇌에서 발현되는 S-100 Beta 유전자의 Polymorphism에 대한 분자생물학적 증거

유민,권오식,신송우 THE KOREAN SOCIETY FOR BIOMEDICAL LABORATORY SCIEN 1998 Journal of biomedical laboratory sciences Vol.4 No.2

쥐 뇌에서 발현되는 S-100 beta 유전자의 다형현상을 조사하였다. Polymerase chain reaction을 위한 주형으로는 뇌에서 분리한 mRNA를 직접 역전사한 cDNA, 또는 rat brain cDNA library에서 분리한 phage DNA를 사용하였다. 증폭된 DNA 절편들은 크기가 기존에 보고되었던 것과 일치하였으나 DNA sequencing을 통한 세부적인 분석 결과 coding region 내에 염기변화 (CAT가 CAC로 변함)가 있음이 확인되었다. 그러나 이들은 모두 histidine을 결정하는 유전암호이기에 단백질의 1차 구조에는 아무런 영향을 미치지 않는 다형현상으로 결론지어졌다. 본 연구는 S-100 beta 단백질에 그 동안 알려지지 않았던 다형현상이 존재함을 시사하는 것으로서 S-100 beta효소 유전자의 전체적인 구조를 이해하기 위한 학문적 자료가 될 것으로 기대된다. We examined mRNAs, isolated from the rat brain, to ascertain if there is any polymorphism for S-100 beta protein gene. As templates for polymerase chain reaction (PCR) the reverse-transcribed cDNA from the rat brain or phage DNAs isolated from the rat brain cDNA libraries were used. Although PCR products turned out to be exactly same as the expected size based on the previously reported mRNA sequence a single base substitution (CAT to CAC) was identified at nucleotide level. This change was considered as polymorphism since it did not cause any change of the primary structure for S-100 beta protein. This result should facilitate the understanding of the overall structure of the gene for S-100 beta protein.

사람의 게놈에 존재하는 Cytochrome P450 2E1의 Retropseudogene에 대한 분자유전학적 증거

유민,신송우 THE KOREAN SOCIETY FOR BIOMEDICAL LABORATORY SCIEN 1998 Journal of biomedical laboratory sciences Vol.4 No.2

Cytochrome P450 2E1 (CYP2E1)의 retropseudogene이 사람에 존재하는 지 확인하기 위해 혈액에서 분리한 DNA를 주형으로 한 polymerase chain reaction (PCR)을 수행하였다. Primer는 CYP2E1 유전자를 기초하여 여러개 제작하되 적절한 조합에 따라 정상유전자와 retropseudogene이 동시에 증폭될 수 있도록 고안하였다. 본 실험의 결과 그 동안 예상은 되었지만 DNA차원에서 미처 확인되지 못하였던 CYP2E1의 retropseudogene을 직접 증폭해낼 수 있었다. 세부 구조는 Southern blotting과 DNA 염기서열 결정에서 최종 분석되었다. PCR 반응으로 증폭된 부분에서는 염기서열이 mRNA와 완전히 일치하고 있는 점으로 미루어서 CYP2E1의 retropseudogene은 비교적 최근에 발생했을 것으로 추정되었다. We have carried out polymerase chain reaction (PCR) to investigate if retropseudogene for CYP2E1 is present in human genome. PCR primers were designed based on the structure of functional CYP2E1 gene and used to amplify both functional gene and retropseudogene in one reaction. From the repeated experiments we were able to amplify a previously unidentified CYP2E1 retropseudogene that was present in human genome. Its detailed structure was confirmed by Southern blotting and DNA sequencing. Nucleotide sequence of this retropseudogene was completely matched up to human liver CYP2E1 mRNA suggesting that the development of this retropseudogene might be a relatively recent event.

주행방향제어를 위한 차선감지장치

유송민 慶熙大學校 材料科學技術硏究所 1993 材料科學技術硏究論集 Vol.6 No.-

Automatic vehicle guidance system (lateral control system) is one of the most promising techniques to the IVHS (intelligent vehicle highway system). Advantages of the technologies are roadway capacity increase and safety and reliability by releaving human streering. The key portions of the system are reference marker and onboard sensing mechanisms identifying the vehicle positional offset form the desired track, ie roadway center line. Technology development trend leading to the current state-of-the-art method is reviewed and compared.

AE 및 가속도 신호를 이용한 리니어 모터 이송시스템의 특성분석

유송민 한국공작기계학회 2000 한국공작기계학회 추계학술대회논문집 Vol.2000 No.-

A brushless linear motor is suitable for operation with higher speed and precision. Since it does not involve mechanical coupling, linear driving force can be applied directly. Conventional PID and fuzzy controllers are implemented and performance results using those controllers are compared. Along with better simulated performance observed using fuzzy controller, further fabrication is to be included with various empirical results. Several system operational characteristics have been observed. Typical nonlinearities as friction, cogging and torque or thrust ripple that might deteriorate system performance would be tackled using presumably effective method such as neural network based learning controller.

마이크로 어셈블리용 6자유도 정렬기의 기구학적 분석 및 디자인

유용환,이문구,이수훈,홍민성,송준엽,이창우 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

This work will develop a 6-DOF precision aligner with small size and high resolution for assembling the micro parts for a mobile electronics. Here, Tiny PicomotorTM actuator that is small and reliable will be applied to this aligner system. The principle of this actuator is PZT that turns a precision thread and then the screw moves linearly. Arrangement of actuators will be a symmetrical based on kinematic design. This paper presents combining two modules of mechanism for the 6-DOF precision aligner. The first is a stage which can control XYθz motion, and the second can control Z motion, in other words, Z tilt motion. According to its specifications, it is expected to satisfy requirement of precision.

경구면역을 통한 항원 특이적 IgA 항체 합성에 있어 Cholera Toxin과 Alginate-Microsphere의 효과

송민형,유진수,권명상,성승룡,김용희,권익찬,정서영,양재명,김평현 大韓免疫學會 1996 大韓免疫學會誌 Vol.18 No.3

Secretory (S-IgA) isotype antibody (Ab) is known to play an essential role in the primary defense against various infectious agents in mucosal tissue. However, it has been mostly unsuccessful in the induction of antigen (Ag)-specific IgA Ab response in this site by peroral vaccination. In the present study, we investigated the effect of cholera toxin (CI) as a mucosal adjuvant and alginates-microspheres as a carrier on BSA-specific IgA Ab response in gut-associated lymphoid tissue`(GALT). Peroral immunization of BSA plus CT conferred a great BSA-specific IgA response but IgG response on intestinal fluid (IF). In contrast, intraperitoneal immunization of BSA with Freund's adjuvant readily induced BSA-specific IgG response but IgA response in IF. Further, number of CT specific IgA-secreting cells was substantially increased in mesenteric lymph node when CT-encapsulated-VI alginates-microspheres was administered perorally. Taken together, these results indicate that peroral immunization of soluble antigen in combination of CT or microspheres significantly enhances antigen-specific IgA response in GALT.

화상처리기법을 이용한 크랭크부 형상측정에 관한 연구

유송민 경희대학교 산학협력기술연구원 1996 산학협력기술연구논문집 Vol.2 No.-

Image processing technique has been applied to identify and analyze crank connector and its hole location relative to edge. Several specimen have been scanned with CCD camera and their top and side image data have been converted for signal analysis. Cross sectional view of the specimen along lateral and longitudinal direction has been extracted from the above data. Filtering technique averaging adjacent data has been applied and both maximum and minimum slope pixel designating first and second edge of the specimen has been identified.

절삭속도 제어를 통한 유연성 디스크 연삭가공에 관한 연구

유송민,김영진 慶熙大學校 材料科學技術硏究所 1998 材料科學技術硏究論集 Vol.11 No.-

A flexible disk grinding process is controlled in order to produce high precision product. A new model was developed considering variable cutting speed. Cutting speed was changed based on the error between the designed disk angle and the current deflected disk angle. Few analysis were made comparing various process parameters such as cutting force, disk angle depth of cut and disk angle with respect to process transition time. Finally, disk angle trend from controlled process was compared with respect to that without any feedback control. Cutting speed control scheme proposed the possibility of simplifying the generation of flat surface compared to variable feed speed control method.