• 제목/요약/키워드: Corresponding author

검색결과 235건 처리시간 0.023초

Molecular Cloning and Characterization of DNA Repair Related Gene in Yeast

  • Kang, Seon-Ah;Park, In-Soon
    • Journal of Life Science
    • /
    • 제10권1호
    • /
    • pp.40-44
    • /
    • 2000
  • The SNF2/SW ATPase/helicase family comprises proteins form a variety of species with in vivo functions, such as transcriptional regulation, maintenance of chromosome stability during mitosis, and various types of DNA repair. Here, we reported the characterization of h게2+gene which was iolated by PCR amplification using the conserved domain of SNF2 motifs. Sequence analysis of PCR product showed striking evolutionary conservation among the SNF2 family of proteins. Two transcripts of 6.7 and 3.4 Lb were detected by Northern blot analysis. furthermore, the intensities of these two bands were increased by ultraviolet(UV) irradiation. These results indicate that the hrp2+ is a novel member of the SNF2 family of proteins and is one of the UV-inducible genes in S. pombe. To determine the level of transcripts of hrp2+ gene during cellular growth, Northern blot analysis were performed. This result indicates that the level of hrp2+transcript reached its maximum before cells entered the exponential growth phase. This suggests that hrp2+ gene is experssed mainly at the early stage of cell growth.

New Thermostable Chitosanase from Bacillus sp.: Purification and Characterization

  • Yoon, Ho-Geun;Ha, Sang-Chul;Lim, Young-Hee;Cho, Hong-Yon
    • Journal of Microbiology and Biotechnology
    • /
    • 제8권5호
    • /
    • pp.449-454
    • /
    • 1998
  • A thennostable chitosanase was purified from Bacillus sp. KFB-C108, by fractionation of 30 to 70% saturation with ammonium sulfate, DEAE-Toyopearl chromatography, Butyl-Toyopearl chromatography, and TSK-Gel HW-55F gel filtration. The purified enzyme showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis, and the molecular weight was estimated to be 48 kDa. The enzyme degraded soluble chitosan and colloidal chitosan, but did not degrade glycol chitosan, chitin, and the other compounds investigated. There was no effect on the chitosanase activity by treatment with chelating agents, alkylating agents, and various metals investigated, and only cobalt ions inhibited the activity. Optimum temperature and pH were $55^{\circ}C$ and 6.5, respectively. The enzyme was stable after heat treatment at $80^{\circ}C$ for 10 min or $70^{\circ}C$ for 30 min and fairly stable in several organic solvents as well. Chitosan was hydrolyzed to $(GlcN)_4$as a major product by incubation with the enzyme.

  • PDF

Probabilistic analysis of spectral displacement by NSA and NDA

  • Devandiran, P.;Kamatchi, P.;Rao, K. Balaji;Ravisankar, K.;Iyer, Nagesh R.
    • Earthquakes and Structures
    • /
    • 제5권4호
    • /
    • pp.439-459
    • /
    • 2013
  • Main objective of the present study is to determine the statistical properties and suitable probability distribution functions of spectral displacements from nonlinear static and nonlinear dynamic analysis within the frame work of Monte Carlo simulation for typical low rise and high rise RC framed buildings located in zone III and zone V and designed as per Indian seismic codes. Probabilistic analysis of spectral displacement is useful for strength assessment and loss estimation. To the author's knowledge, no study is reported in literature on comparison of spectral displacement including the uncertainties in capacity and demand in Indian context. In the present study, uncertainties in capacity of the building is modeled by choosing cross sectional dimensions of beams and columns, density and compressive strength of concrete, yield strength and elastic modulus of steel and, live load as random variables. Uncertainty in demand is modeled by choosing peak ground acceleration (PGA) as a random variable. Nonlinear static analysis (NSA) and nonlinear dynamic analysis (NDA) are carried out for typical low rise and high rise reinforced concrete framed buildings using IDARC 2D computer program with the random sample input parameters. Statistical properties are obtained for spectral displacements corresponding to performance point from NSA and maximum absolute roof displacement from NDA and suitable probability distribution functions viz., normal, Weibull, lognormal are examined for goodness-of-fit. From the hypothesis test for goodness-of-fit, lognormal function is found to be suitable to represent the statistical variation of spectral displacement obtained from NSA and NDA.

다양한 경계조건을 갖는 복합적층판의 정확한 고유진동수를 얻기 위한 간편 해석법 (A Simple Method of Obtaining "Exact" Values of the Natural Frequencies of Vibration for Some Composite Laminated Structures with Various Boundary Condition)

  • 김덕현;원치문;이정호
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2001년도 추계학술발표대회 논문집
    • /
    • pp.9-12
    • /
    • 2001
  • Composite materials can be used economically and efficiently in broad civil engineering applications when standards and processes for analysis, design, fabrication, construction and quality control are established. Many of the bridge systems, including the girders and cross-beams, and concrete decks behave as the special othotropic plates. Such systems with boundary conditions other than Navier or Levy solution types, or with irregular cross sections, analytical solution is very difficult to obtain. Numerical method for eigenvalue problems are also very much involved in seeking such a solution. A method of calculating the natural frequency corresponding to the first mode of vibration of beam and tower structures with irregular cross-sections was developed and reported by the author in 1974 Recently, this method was extended to two dimensional problems including composite laminates, and has been applied to composite plates with various boundary conditions with/without shear deformation effects and reported at several international conferences including the Eighth Structures Congress of American Society of Civil Engineers in 1990. In this paper, the result of application of this method to the special orthotropic plates with various boundary condition is presented.

  • PDF

한국 동해안의 변화특성 (A Study on Characteristics of Coastline Change in Eastern Coast Korea)

  • 이종태
    • 수산해양기술연구
    • /
    • 제15권1호
    • /
    • pp.35-42
    • /
    • 1979
  • This paper concerns the receding of the eastern coastline of Korean peninsula at a macroscopic point of view, the result is as following. 1. Eastern coast is gradually developed from maturity stage to full maturity stage. 2. The coastline recession due to sea level rise is amounted to the receding distance, x=0.045 m per yr. 3. The author proposes another classification from the new view point, which is classified by comparing quantities between river supplying sediment loads, and the littoral drifting due to wave actions. According this, eastern coast is receding(Type Q-A), and we could find it's geomorphological characteristics. 4. The general piofile of eastern coast sand beach is erosional storm profile(Type I) which accompany offshore bar. 5. From the wave measuring data of eastern coast(Hoopo port), I can derive the linear regression line of the exceedance probability of wave height from the log-normal distribution. $z=O. 113+4.335 log_lo H, r=0.983.$ Above equation made it possible to estimate $\omega[=P(H>H_c)]for the effective wave height H_c=2. Om4, 4. Om and their corresponding values are considerable (7.8%, 0.3%) 6. Eastern coastline certainly have the tendency of erosive and receding, owing to the sea level rise, poor sediment source and effective wave actions. It's very desirable to survey coastline evolution for a long time systematically, in order to make more elaborate diagnosis.

  • PDF

Estrogen대사 효소의 유전자 다형성과 한국인 유방암 환자의 유전적 감수성에 대한 연구 (Genetic polymorphism of Estrogen metabolising enzymes and individual genetic susceptibility to breast cancer in Korean)

  • 김현준;이수진;공구
    • 한국환경성돌연변이발암원학회지
    • /
    • 제23권1호
    • /
    • pp.23-29
    • /
    • 2003
  • To determine the frequencies of the genotypes of estrogen metabolising enzyme (CYP17, CYP1A1, CYP1B1, and COMT) and to identify the high-risk genotypes of these metabolic enzymes to breast cancer in Korean, the author has analysed 115 breast cancer patients and corresponding age and sex matched heathy controls using polymerase chain reaction-restiction fragment length polymorphism (PCR-RFLP). A2/A2 genotype in CYP17 polymorphism, m2/m2 genotype in CYP1A1 polymorphism, and Val/Val genotype in CYP1B1 had 0.95, 1.40 and 0.76 relive risks to breast cancer comparing with reference genotypes of each polymorphism, respectively. Among the genotypes of COMT enzyme polymorphism, L/H and L/L genotypes had 0.97 and 1.54 relative risks to breast cancer, respectively. According to the number of high risk genotype, the patients with one or two putative high risk genotypes had 0.95 and 1.94 relative risks to breast cancer, respectively. This study have demonstrated the unique frequency of genotypes of estrogen metabolizing enzyme in Korean healthy women, which will provide the basic data and insights to study the estrogen related conditions in Korean women including breast and endometrial cancers. And it also indicates that the well-known high risk genotypes of estrogen metabolizing enzymes are not significantly associated with the development of breast cancer in Korean women.

  • PDF

Terrein의 etoposide에 의해 유도된 apoptosis 저해효과 (Anti-apoptotic Effects of Terrein on Etoposide-induced Apoptosis of U937 Human Leukemia Cells)

  • 이충환;이호재;김진희;김현아;고영희
    • 한국미생물·생명공학회지
    • /
    • 제28권2호
    • /
    • pp.87-91
    • /
    • 2000
  • 미생물로부터 U937 세포주의 etoposide에 유발된 apoptosis 저해물질을 탐색한 결과 곰팡이 F80834 균주를 선발하였다. 균주 배양액으로부터 저해물질을 분리한 후 UV, EIMS, 1H-NMR, 13C-NMR, DEPT 등의 기기분석을 실시한 결과 terrein으로 동정되었다. 이 물질은 $IC_{50}$ $20\mu\textrm{g}/ml$의 농도로 U937 세포주의 etoposide에 의한 caspase 3 유도를 저해하였다. Etoposide에 의한 세포의 사멸도 IC50 $10\mu\textrm{g}/ml$ 농도로 저해하였으며, 동일한 농도 조건에서 단독 처리시 세포 독성을 나타내지 않았다.

  • PDF

Aspergillus sp. F184가 생산하는 Xanthine Oxidase 저해제에 관한 연구 (Studies on Xanthine Oxidase Inhibitor Produced from Aspergillus sp. F184)

  • 박시형;윤상웅;박정민;옥승호;유주현;배동훈
    • 한국미생물·생명공학회지
    • /
    • 제28권2호
    • /
    • pp.92-96
    • /
    • 2000
  • 통풍과 oxygen free radical의 독성에 관여하는 xanthine oxidase에 대한 새로운 저해물질의 탐색 및 개발을 목적으로 본 연구에서 선택분리한 Aspergillus sp. F184가 생산하는 저해물질을 분리.정제하고 구조를 결정하였으며 효소저해활성을 조사하였다. 본 균주를 배양 후 배양액을 여과하여 균체와 배양액을 분리하고 균체를 acetone으로 추출하고 감압농축하고 남은 수용액층을 배양액과 합쳐 HP-20 adsorption column chromatography, ethyl acetate 추출, silica gel column chromatography, 결정화 등을 실시하여 xanthine oxidase에 대한 저해물질을 분리, 정제하였다. 본 저해물질의 구조를 NMR 및 MS 스펙트럼을 측정하여 분석한 결과 5,6-epoxy-2-hydroxy-3-methyl-2-cyclohexene-1,4-dione으로서 terreic acid로 동정되었다. Terreic acid의 xanthine oxidase에 대한 저해활성을 조사한 결과 IC50가 1.1$\times$10-7M로서 기존의 저해제인 allopurinol과 유사하였다. 이에 terreic acid에 의한 xanthine oxidase 저해활성은 보고된 바가 없기에 새로운 통풍치료제로서의 가능성이 있음을 보고한다.

  • PDF

어린이도서관에 있어서 이용자의 자주적 관리에 의한 공간변화에 관한 연구 (A Study on Space alteration by User's Independent Management in Children's Library)

  • 천혜선;이정미;곽동화;임채진;이상복
    • 한국실내디자인학회논문집
    • /
    • 제18권2호
    • /
    • pp.93-101
    • /
    • 2009
  • This study is including the independent project, "building children's library of the town" that is conducted by a local resident. The study object is the contents of the "design workshop for library planning" and the general process during one year since the opening. This study is delivering "information of children's library" through the work-shop and is conducting the role of a professional space planner by measuring the blueprint. Thus, the study could be conducted with synthetic viewpoint on each library. The followings are the results from the study. First, there were various space operations and a variety of programs in the case library that is independently managed. This is directing to "the constructive and active space usage" by the users and finally results in positive circulation. Secondly, there is a change through the process of execution and operation in the library construction plan. There are needs for the flexible space expansion and adjustment, modifiable furniture layout and design and various keeping areas because there is on-going tendency of corresponding space change. The third, the author could draw more practicable consideration points for space planning by looking at the trend of space change in Transactionist viewpoint. Thus, this study is very meaningful in terms of planning of sustainable public areas.

한국산 밀립의 휘발성 성분과 Carotene류의 분석 (Volatile Compounds and Carotenes Analysis of Korean Beeswax)

  • 권혜순
    • 한국응용과학기술학회지
    • /
    • 제15권4호
    • /
    • pp.63-69
    • /
    • 1998
  • The beeswax sample was collected from the beehives, isolated and then refined. The first step of producing beeswax was to separate honey from beehives. The beehives which were cut put in hot water. The upper layer was crude beeswax, which was treated with phosphoric acid. The crude beeswax was purified through the bleaching. The objectives of this study are to identify headspace volatile compounds and to know the contents of ${\alpha}$-carotenes and ${\beta}$-carotenes of korean beeswax. Headspace volatile compounds of Korean beeswax were measured by using the combination of dynamic headspace sampler (DS 5000, Donam System Inc.), gas chromatography and mass selective detector (HP5890 & 5971, Hewlett Packard). Seventy five compounds identified from about 100 peaks by analyzing the purified beeswax were 60 hydrocarbons, 8 carbonyls, 4 essential oils, 3 esters. Carotenes of Korean beeswax were analyzed by using High Performance Liquid Chromatography (Waters Inc.). As A result, the content of ${\alpha}$-carotenes and ${\beta}$-carotenes were 0.07ppm, 0.011ppm individually.