Synchrotron Light Source Application in Life Science

Synchrotron Light Source Application in Life Sciences [ 下載 PDF ]

Wen-Guey Wu

 

Synchrotron Radiation Circular Dichroism End Station and Its Applications [ 下載 PDF ]

Su-Yu Chiang, Cheng-I Lee, Hok-Sum Fung, Wan-Lin Tsai, Shiang-Wen Luo

Circular dichroism spectroscopy is a simple and quick method for studying structural alterations of optical materials in aqueous solution under various experimental conditions, for example, as a function of temperature or chemical denaturant. Applications in biochemistry and structural biology include characterization of proteins and their conformation changes and dynamics, as well as examining macromolecular interactions and functions of biological membranes. Synchrotron radiation circular dichroism (SRCD) spectroscopy requires small amount of samples and can provide new information in shorter wavelength region by taking advantages of synchrotron radiation-highly linear polarization, high photon flux and continuous tunability in the vacuum ultraviolet region; accordingly, this spectroscopic method can further explore new research areas, particularly in structural and functional genomics. In this article, we will introduce the new SRCD end station at SEYA beamline in NSRRC and its applications.

Recent Progress of Protein X-Ray Crystallography and Synchrotron Radiation [ 下載 PDF ]

Yen-Ju Chen

Protein structures play important roles in understanding their functions and activities. Structural research is a corner stone in every genomic project worldwide. Among all the techniques used to solve protein structures, protein X-ray crystallography is the most widely used and indispensable. And synchrotron raidation is an essential tool for protein X-ray crystallography. In this article, latest techinques will be introduced, including using sulfur-SAD for phase problem, expressing proteins with cell-free system and crystalizing membrane protein with lipidic cubic phase. Two examples of recently solved membrane proteins will show the progress of protein crystallography in last few years.

Automation of High-Throughput Protein Purification for X-Ray Crystallography Study [ 下載 PDF ]

Szu-Heng Liu, Shih-Fand Huang, Takun Yudaw, Kuan-Yeu Pan, Yi-Hung Lin

Advances in genomics research provide valuable information about the composition of proteins, but little about their structures and most crucially, little concerning their functions. Thus, it is essential to know their threedimensional structures and further to understand how and why proteins function as they do. To date, structural genomics is a field of research that has been established in particular for deciphering of the 3-D structure of proteins via a high-throughput methodologies and techniques. The critical challenge in the studies of structural genomics in general, is the availability of milligram-quantity and most importantly high-quality soluble monodisperse proteins. The choice of protein purification and handling procedures plays a critical role in obtaining high-quality proteins. In this regard, we introduce AKTA explorer 3D and AKTAxpress workstations that has been successfully applied to many structural genomics centers, capable of performing multidimensional chromatography. Various purification strategies, their design and their implementation are discussed in this study.

Applications of Hard X-Ray Absorption Spectroscopy in Life Science [ 下載 PDF ]

Jyh-Fu Lee, I-Jui Hsu, Steve Sheng-Fa Yu, Feng-Chun Lo, Meiyi Li, Ying-Jen Shiu

Thanks to the high intensity and energy tunability of synchrotron radiation, X-ray absorption spectroscopy (XAS) has become a powerful tool for probing the electronic and local atomic structures of various materials. In this article, we briefly introduce the principles and data analysis procedures of XAS. Besides, several XAS beamlines and endstations at National Synchrotron Radiation Research Center are described. Some examples serve to illustrate the applications of XAS in life science.

X-Ray Diffraction/Scattering on Bio-Membrane Structure Study [ 下載 PDF ]

Ming-Tao Lee

Bio-membrane is the important component of cell and its structure is the key issue in biology field. Due to the scale of structure is about 3–5 nm, X-ray is the powerful tool to measure the structure of membrane. Using X-ray diffraction to determine the electron density profile of lamellar membrane sample, we can study fine structure of bio-membrane. X-ray scattering on small unilamellar vesicles (SUVs) sample can be used to probe membrane thickness in solution. The conditions are more close to which the real cell live in. Synchrotron radiation X-ray source has good properties of high flux, high collimation and small beam size. Using synchrotron light source on biological sample study should be most advantaged.

Overview on the Development of Protein Structure Determination by Using Synchrotron X-Ray Crystallography from a Viewpoint of the Growth of Protein Structural Data [ 下載 PDF ]

Kuan-Yeu Pan, Chen-hsiung Chan

Most of the macromolecular structures deposited in Protein Data Bank (PDB) are determined by X-ray crystallography. In recent years, the growth rate of protein structural data has slowed, implying that the enhancement of techniques for novel protein structure determination is desired. The integrated technology platform for biocrystallography developed by advanced synchrotron radiation facilities provides the advantage of exploring innovative methods for novel structures discovery to enhance the growth rate of PDB.

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Application of Electron-Beam Technology on Materials Interface Engineering [ 下載 PDF ]

Jong-Lih Li, Chieh-Hsiung Kuan

An integrated electron-beam technology has been successfully applied on the area of materials interface engineering. And it is based on combing the advantages of 'top down' and 'bottom up' approaches in the research and development (R/D) of the nano science and technology. In the applications, the common nature with high resolution of the electron-beam systems has been fully utilized in the fabrication and materials investigation of the interface structures. Moreover, a newly developed interface with the patterned structures on the surface of the substrate, unlike the conventionally planar one, and an evolved R/D configuration for the materials interface engineering are proposed. Through a practical example, it is demonstrated that electron-beam technology has a great potential in the application on the area of the materials interface. The proposed materials interface structure can also provide an alternative to improve the metal-semiconductor contact conductance and a possibility to explore the mechanism of the metal-semiconductor interface further.

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The Ions Motion of the Capillary Electrophoretic Separation [ 下載 PDF ]

Ying Chou, Ruey-Jen Yang

The so-called electrophoretic separation is described as following: after applying an electrical potential, the sample ions will be separated because of the different mobility velocity. The first developed method was the moving boundary electrophoresis (MBE) which had success in serum separation. Moreover, the MBE technique had many contributions in the early biotech studies. By extending the concept of MBE technique and employing the uniform buffers to separating the sample electrophoresis, the zone electrophoresis (ZE) was developed. The isotachoporesis (ITP) technique is based on the separation in a discontinuity form between two buffer solutions and results in separation of samples. The isoelectric focusing (IEF) is a method that concentrates the ampholyte sample by the pH gradient introduced in the background ampholytes. This article will exhibit these electrophoretic separation methods by using a high resolution numerical scheme.

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Stroboscopic Illumination Photoelastic Modulated Imaging Ellipsometry/Polarimetry [ 下載 PDF ]

Yu-Faye Chao, Chien-Yuan Han, Hsiu-Ming Tsai

A novel stroboscopic illumination technique is applied in a photoelastic modulated ellipsometry/polarimetry to conquer the slow imaging processing of charge-coupled device camera system and form a fast imaging ellipsometry/polarimetry. The synchronized ultrastable short pulse is used to freeze the intensity variation of the PEM modulated signal. The 2D thickness profile of a static patterned SiO₂ thin film on silicon substrate and the drainage behavior of matching oil on silicon wafer were studied by this imaging ellipsometry. In addition to the ellipsometry, a Mueller matrix polarimetry is also constructed by the similar technique. The drying process of Echinodorus uruguayensis is analyzed by the polarimetry. Lu-Chipman's polar decomposition technique is used to remove the depolarization, which is caused by the multiple scattering in the medium. Under drying process, the variation of linear birefringence of leaf is observed by this imaging polarimetry.

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Oblique Incident Interferometric Measurement for Long-Stripped Flat [ 下載 PDF ]

Hui-Jean Kuo, Shenq-Tsong Chang, Ho-Lin Tsay

Peak-to-valley surface wavefront error of a long-stripped flat can be derived by oblique incident setup in case that dimension of the test flat is larger than the beam size of interferometer. Error of measurement in this setup was demonstrated to be lower than (1/10)λ. With proper choice of incident angle, test dimension can be up to more than twofold of beam size.