• 제목/요약/키워드: Biological systems

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Trametes versicolor KCTC 16781에 의한 다양한 염료의 색도제거 특성 (Enzymatic Decolorization of Various Dyes by Trametes versicolor KCTC 16781)

  • 박철환;이유리;김탁현;이명구;이병환;이진원;김상용
    • KSBB Journal
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    • 제18권5호
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    • pp.398-403
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    • 2003
  • 고체배양을 통해 10종의 균주 중에서 선별된 고활성 균주인 T. versicolor KCTC 16781은 100 mg/L의 6가지 염료(reactive blue 19, reactive blue 49, reactive black 5, acid black 52, reactive orange 16, and acid violet 43)를 15일 이내에 효율적으로 분해하였다. T. versicolor KCTC 16781은 액체배양에서 반응 2-3일 이내에 6가지 염료의 색도를 100% 제거시켰으며, 배양 초기에 빠른 속도로 효소를 생산하여 높은 활성을 보였다. 이로 인해 색도제거 속도가 기존의 연구에 보고된 결과들보다 우수함을 입증하였다. 서로 다른 종류의 염료분해 실험에서, 효소활성이 반응 초기에 작은 차이를 보였지만, 최대 효소활성에 도달한 후의 값이 2.0$\pm$0.5 U/mL의 범위에 들어 염료의 종류에 관계없이 비슷한 범위의 활성을 보이는 것을 확인할 수 있었다. 염료의 색도제거가 완벽하게 이루어진 후에도 효소활성은 감소하지 않았으며, 배양 말기까지 2.0 U/mL 이상의 효소활성을 유지하여 고농도의 염료를 제거할 수 있는 가능성을 보였다.

식이지방이 생체막 구조와 기능에 미치는 영향 (Effect of Dietary Fat on Structure and Function of Mammalian Cell Membrane)

  • 조성희
    • 한국식품영양과학회지
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    • 제13권4호
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    • pp.459-468
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    • 1984
  • The currently accepted model of membrane structure proposes a dynamic, asymmetric lipid matrix of phospholipids and cholesterol with globular proteins embedded across the membrane to various degrees. Most phospholipids are in the bilayer arrangement and also closely associated with integral membrane proteins or loosely associated with peripheral proteins. Biological functions of membrane, such as membrane-bound enzyme functions and transport systems, are influenced by the membrane physical properties, which are determined by fatty acid composition of phospholipids, polar head group composition and membrane cholesterol content. Polar and non-polar region of the phospholipid molecule can interact, with changes in the conformation of a membrane-associated protein altering either its catalytic activity or the protein's interaction with other membrane proteins. Mammalian dietary studies attempted to change the lipid composition of a few cell membranes have shown comparisons, using essential fatty acid-deficient diets. In recent years, Clandinin and a few other workers have pioneered the study proving the influence of dietary fat fed in a nutritionally complete diet on composition of phospholipid classes of cell membrane. Modulation caused by diet fat was rapid and reversible in phospholipid fatty acyl composition of membranes of cardiac mitochondria, liver cell, brain synaptosome and lymphocytes. These changes were at the same time, accompanied by variety of membrane associated functions controlled by membrane-bound enzymes, tranporter and receptor proteins. The findings suggest the basic concept of the necessity of dietary fatty acid balance if consistency of optimal membrane structural lipid composition is to be maintained, as well as the overall inadequacy of describing the nutritional-biochemical quality of a dietary fat solely by its content of linoleic acid. Furthermore, they give light on the possible application to clinical and preventive medicine.

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Comparative Analysis of Envelope Proteomes in Escherichia coli B and K-12 Strains

  • Han, Mee-Jung;Lee, Sang-Yup;Hong, Soon-Ho
    • Journal of Microbiology and Biotechnology
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    • 제22권4호
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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.

Production of a Recombinant Laccase from Pichia pastoris and Biodegradation of Chlorpyrifos in a Laccase/Vanillin System

  • Xie, Huifang;Li, Qi;Wang, Minmin;Zhao, Linguo
    • Journal of Microbiology and Biotechnology
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    • 제23권6호
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    • pp.864-871
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    • 2013
  • The recombinant strain P. pastoris GS115-lccC was used to produce laccase with high activity. Factors influencing laccase expression, such as pH, methanol concentration, copper concentration, peptone concentration, shaker rotate speed, and medium volume were investigated. Under the optimal conditions, laccase activity reached 12,344 U/L on day 15. The recombinant enzyme was purified by precipitating and dialyzing to electrophoretic homogeneity, and was estimated to have a molecular mass of about 58 kDa. When guaiacol was the substrate, the laccase showed the highest activity at pH 5.0 and was stable when the pH was 4.5~6.0. The optimal temperature for the laccase to oxidize guaiacol was $60^{\circ}C$, but it was not stable at high temperature. The enzyme could remain stable at $30^{\circ}C$ for 5 days. The recombinant laccase was used to degrade chlorpyrifos in several laccase/mediator systems. Among three synthetic mediators (ABTS, HBT, VA) and three natural mediators (vanillin, 2,6-DMP, and guaiacol), vanillin showed the most enhancement on degradation of chlorpyrifos. Both laccase and vanillin were responsible for the degradation of chlorpyrifos. A higher dosage of vanillin may promote a higher level of degradation of chlorpyrifos, and the 2-step addition of vanillin led to 98% chlorpyrifos degradation. The degradation of chlorpyrifos was faster in the L/V system ($k_{obs}$ = 0.151) than that in the buffer solution ($k_{obs}$ = 0.028).

Structural Analyses of Zinc Finger Domains for Specific Interactions with DNA

  • Eom, Ki Seong;Cheong, Jin Sung;Lee, Seung Jae
    • Journal of Microbiology and Biotechnology
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    • 제26권12호
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    • pp.2019-2029
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    • 2016
  • Zinc finger proteins are among the most extensively applied metalloproteins in the field of biotechnology owing to their unique structural and functional aspects as transcriptional and translational regulators. The classical zinc fingers are the largest family of zinc proteins and they provide critical roles in physiological systems from prokaryotes to eukaryotes. Two cysteine and two histidine residues ($Cys_2His_2$) coordinate to the zinc ion for the structural functions to generate a ${\beta}{\beta}{\alpha}$ fold, and this secondary structure supports specific interactions with their binding partners, including DNA, RNA, lipids, proteins, and small molecules. In this account, the structural similarity and differences of well-known $Cys_2His_2$-type zinc fingers such as zinc interaction factor 268 (ZIF268), transcription factor IIIA (TFIIIA), GAGA, and Ros will be explained. These proteins perform their specific roles in species from archaea to eukaryotes and they show significant structural similarity; however, their aligned amino acids present low sequence homology. These zinc finger proteins have different numbers of domains for their structural roles to maintain biological progress through transcriptional regulations from exogenous stresses. The superimposed structures of these finger domains provide interesting details when these fingers are applied to specific gene binding and editing. The structural information in this study will aid in the selection of unique types of zinc finger applications in vivo and in vitro approaches, because biophysical backgrounds including complex structures and binding affinities aid in the protein design area.

Development of Integrated Biomedical Signal Management System Based on XML Web Technology

  • Lee Joo-sung;Yoon Young-ro
    • 대한의용생체공학회:의공학회지
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    • 제26권6호
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    • pp.399-406
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    • 2005
  • In these days, HIS(Hospital Information System) raise the quality of medical services by effective management of medical records. As computing environment was developed, it is possible to search information quickly. But, standard medical data exchange is not completed between medical clinic and another organ so far. In case of patient transfer, past medical record was not efficiently transmitted. It be feasible treatment delay or medical accident. It is trouble that medical records is transferred by a person and communicate with each other. Extensible Markup Language (XML) is a simple, very flexible text format derived from SGML. Originally designed to meet the challenges of large-scale electronic publishing, XML is also playing an increasingly important role in the exchange of a wide variety of data on the Web and elsewhere. Form in system of company product, relative organs that handle bio-signal data is each other dissimilar and integration and to transmit to supplement bottleneck this research uses XML. In this study, it is discussed about sharing of medical data using XML web technology to standard medical record between hospital and relative organization The data structure model was designed to manage bio-signal data and patient record. We experimented about data transmission and all-in-one between different systems (one make use of MS-SQL database system and the other manage existent bio-signal data in itself form in file in this research). In order to search and refer medical record, the web-based system was implemented. The system that can be shared medical data was tested to estimate the merits of XML. Implemented XML schema confirms data transmission between different data system and integration result.

치매환자를 위한 대화 보조 시스템 (Communication Aid System For Dementia Patients)

  • Sung-Ill Kim;Byoung-Chul Kim
    • 대한의용생체공학회:의공학회지
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    • 제23권6호
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    • pp.459-465
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    • 2002
  • 본 연구는 치매노인 환자들과 간호사들의 생활의 질의 향상에 목표를 준다. 이를 위해 치매환자를 위한 대화보조 시스템이 제안되었고, 이 시스템은 주로 세가지 모듈, 즉, 음성인식엔진, 화상 에이전트, 간호 시케쥴에 의해 구분된 대화 데이터베이스 등으로 구성되었다. 남성 치매환자에 시스템을 도입함에 의해서 간호시설의 실제적인 환경에서 시스템의 평가가 이루어졌고 시스템이 도입되었을 때와 되지 않았을 때의 비교연구도 실시하였다. 치료 전문가(occupational therapist)들이 비디오 촬영을 통해서 대상자의 반응을 평가한 결과, 치매환자의 요구를 충족시키는데 있어서 대화 시스템이 전문간호사들보다 더 응답적이었다는 것을 보여준다. 게다가, 시스템을 도입함에 의해서 대상자의 발화를 유도하는 빈도가 증가함을 알 수 있었다.

초음파 의료 영상에서 합성 Sinc 음장 집속방법의 실험적 고찰 (An Experimental Study of the Synthetic Sinc Wave in Ultrasonic Imaging)

  • 이광주;정목근
    • 대한의용생체공학회:의공학회지
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    • 제23권3호
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    • pp.243-251
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    • 2002
  • 합성 싱크 음장은 선형지연을 가지는 펄스 평면파를 송신한다. 송신집속은 각각 다른 시간에 송신된 진행방향이 다른 평면파들에 대한 수신신호를 모두 저장하고 있다가 합성집속 방법을 이용한다 이러한 송신 집속 방법은 송신시 전체의 소자를 동시에 사용함으로 높은 SNR을 얻을수 있고. 양방향 동적집속이 가능하다. 본 논문에서는 합성싱크음장 집속방법을 구현하기위한 문제점을 고찰하고, 5MHz의 선형변환기를 이용한 초음파 영상진단기에서 펜텀과 인체의 영상에 대하여 합성싱크음장 집속방법을 실험으로 검증하였다 펜텀 영상의 경우 기존의 방법에 비하여 더 좋은 해상도로 더 깊이 영상화 할 수 있었다. 인체 영상의 경우 인체의 움직임과 위상수차(phase aberration) 등으로 인한 효과로 해상도는 떨어지지만. 기존의 집속방법에 대하여 5배 이상의 frame 율의 속도로 영상을 얻어도 기존의 방법과 비슷한 해상도를 얻을 수 있었다

Controller for Single Line Tracking Autonomous Guidance Vehicle Using Machine Vision

  • Shin, Beom-Soo;Choi, Young-Dae;Ying, Yibin
    • Agricultural and Biosystems Engineering
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    • 제6권2호
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    • pp.47-53
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    • 2005
  • AMachine vision is a promising tool for the autonomous guidance of farm machinery. Conventional CCD camera for the machine vision needs a desktop PC to install a frame grabber, however, a web camera is ready to use when plugged in the USB port. A web camera with a notebook PC can replace existing camera system. Autonomous steering control system of this research was intended to be used for combine harvester. If the web camera can recognize cut/uncut edge of crop, which will be the reference for steering control, then the position of the machine can be determined in terms of lateral offset and heading angle. In this research, a white line was used as a cut/uncut edge of crop for steering control. Image processing algorithm including capturing image in the web camera was developed to determine the desired travel path. An experimental vehicle was constructed to evaluate the system performance. Since the vehicle adopted differential drive steering mechanism, it is steered by the difference of rotation speed between left and right wheels. According to the position of vehicle, the steering algorithm was developed as well. Evaluation tests showed that the experimental vehicle could travel within an RMS error of 0.8cm along the desired path at the ground speed of $9\sim41cm/s$. Even when the vehicle started with initial offsets or tilted heading angle, it could move quickly to track the desired path after traveling $1.52\sim3.5m$. For turning section, i.e., the curved path with curvature of 3 m, the vehicle completed its turning securely.

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반복 하중 후 골밀도 감소에 따른 척추경 나사못의 고정력(Pullout Strength)감소 형태 분석 (Biomechanical analysis of pullout strength of the pedicle screws in relation to change bone mineral density)

  • 정덕영;이성재;김동수;신정욱;김원중;석세일
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.155-156
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    • 1998
  • Screw loosening and subsequent pullout can be attributed to the reduction in bone mineral density in the vertebrae manifested by osteoporosis in which the decrease in fixation strength between the cancellous bone and screw threads are accelerated by repeated loads exerted by patients own weight and activities following the surgery. In this study, the change in pullout strength of the pedicle screws was investigated before and after repeated loads were imparted. For this purpose. Diapason pedicle screws $(6.7\times40mm)$ were inserted onto fresh porcine spine specimens (T1-L5) after bone mineral density was measured using a DEXA. With an MTS, an axial load was applied at a loading rate of 0.33mm/sec until failure to measure the maximum pullout strength. Flexion moment of 7.5N-m was then imparted at 0.5Hz for 2000 cycles. It was found that the maximum pullout strength was exponentially related to BMD regardless of load types ($107.71\;\times\;\exp^{(1.43{\times}BMD)}r^2=0.93$, P<0.0001 without repeated load; ($107.71\;\times\;\exp^{(2.19{\times}BMD)}r^2=0.78$, P<0.0001 with repeated load). The results suggest that the reduction in pullout strength for pedicle screws is far more prominent in osteoporotic spine than in normal spine especially as number of repeated load was increased. More importantly, it was demonstrated that the level of bone mineral density and the activity level of the patient should be evaluated in more detail for successful implementation of pedicle screw systems in spinal surgery.

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