Academic literature on the topic 'X-ray crystallography'

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Journal articles on the topic "X-ray crystallography"

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Bombicz, Petra. "X-ray crystallography." Crystallography Reviews 22, no. 1 (September 24, 2015): 79–81. http://dx.doi.org/10.1080/0889311x.2015.1082129.

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Wright, Jonathan. "X-ray crystallography." Crystallography Reviews 22, no. 4 (October 2016): 296–99. http://dx.doi.org/10.1080/0889311x.2016.1251424.

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Smyth, M. S. "x Ray crystallography." Molecular Pathology 53, no. 1 (February 1, 2000): 8–14. http://dx.doi.org/10.1136/mp.53.1.8.

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Helliwell, J. R. "X-ray crystallography." Physics Education 30, no. 6 (November 1995): 355–60. http://dx.doi.org/10.1088/0031-9120/30/6/007.

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Zou, Xiaodong, and Sven Hovmöller. "Electron crystallography: imaging and single-crystal diffraction from powders." Acta Crystallographica Section A Foundations of Crystallography 64, no. 1 (December 21, 2007): 149–60. http://dx.doi.org/10.1107/s0108767307060084.

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The study of crystals at atomic level by electrons – electron crystallography – is an important complement to X-ray crystallography. There are two main advantages of structure determinations by electron crystallography compared to X-ray diffraction: (i) crystals millions of times smaller than those needed for X-ray diffraction can be studied and (ii) the phases of the crystallographic structure factors, which are lost in X-ray diffraction, are present in transmission-electron-microscopy (TEM) images. In this paper, some recent developments of electron crystallography and its applications, mainly on inorganic crystals, are shown. Crystal structures can be solved to atomic resolution in two dimensions as well as in three dimensions from both TEM images and electron diffraction. Different techniques developed for electron crystallography, including three-dimensional reconstruction, the electron precession technique and ultrafast electron crystallography, are reviewed. Examples of electron-crystallography applications are given. There is in principle no limitation to the complexity of the structures that can be solved by electron crystallography.
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Nam, Ki-Hyun. "Approach of Serial Crystallography II." Crystals 11, no. 6 (June 9, 2021): 655. http://dx.doi.org/10.3390/cryst11060655.

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Serial crystallography (SX) is an emerging X-ray crystallographic method for determining macromolecule structures. It can address concerns regarding the limitations of data collected by conventional crystallography techniques, which require cryogenic-temperature environments and allow crystals to accumulate radiation damage. Time-resolved SX studies using the pump-probe methodology provide useful information for understanding macromolecular mechanisms and structure fluctuation dynamics. This Special Issue deals with the serial crystallography approach using an X-ray free electron laser (XFEL) and synchrotron X-ray source, and reviews recent SX research involving synchrotron use. These reports provide insights into future serial crystallography research trends and approaches.
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Nam, Ki. "Sample Delivery Media for Serial Crystallography." International Journal of Molecular Sciences 20, no. 5 (March 4, 2019): 1094. http://dx.doi.org/10.3390/ijms20051094.

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X-ray crystallographic methods can be used to visualize macromolecules at high resolution. This provides an understanding of molecular mechanisms and an insight into drug development and rational engineering of enzymes used in the industry. Although conventional synchrotron-based X-ray crystallography remains a powerful tool for understanding molecular function, it has experimental limitations, including radiation damage, cryogenic temperature, and static structural information. Serial femtosecond crystallography (SFX) using X-ray free electron laser (XFEL) and serial millisecond crystallography (SMX) using synchrotron X-ray have recently gained attention as research methods for visualizing macromolecules at room temperature without causing or reducing radiation damage, respectively. These techniques provide more biologically relevant structures than traditional X-ray crystallography at cryogenic temperatures using a single crystal. Serial femtosecond crystallography techniques visualize the dynamics of macromolecules through time-resolved experiments. In serial crystallography (SX), one of the most important aspects is the delivery of crystal samples efficiently, reliably, and continuously to an X-ray interaction point. A viscous delivery medium, such as a carrier matrix, dramatically reduces sample consumption, contributing to the success of SX experiments. This review discusses the preparation and criteria for the selection and development of a sample delivery medium and its application for SX.
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Nam, Ki Hyun. "Serial X-ray Crystallography." Crystals 12, no. 1 (January 13, 2022): 99. http://dx.doi.org/10.3390/cryst12010099.

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Serial crystallography (SX) is an emerging technique to determine macromolecules at room temperature. SX with a pump–probe experiment provides the time-resolved dynamics of target molecules. SX has developed rapidly over the past decade as a technique that not only provides room-temperature structures with biomolecules, but also has the ability to time-resolve their molecular dynamics. The serial femtosecond crystallography (SFX) technique using an X-ray free electron laser (XFEL) has now been extended to serial synchrotron crystallography (SSX) using synchrotron X-rays. The development of a variety of sample delivery techniques and data processing programs is currently accelerating SX research, thereby increasing the research scope. In this editorial, I briefly review some of the experimental techniques that have contributed to advances in the field of SX research and recent major research achievements. This Special Issue will contribute to the field of SX research.
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Rousse, Antoine, Christian Rischel, and Jean-Claude Gauthier. "Femtosecond x-ray crystallography." Reviews of Modern Physics 73, no. 1 (January 2, 2001): 17–31. http://dx.doi.org/10.1103/revmodphys.73.17.

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Romoli, Filippo, Estelle Mossou, Maxime Cuypers, Peter van der Linden, Philippe Carpentier, Sax A. Mason, V. Trevor Forsyth, and Sean McSweeney. "SPINE-compatible `carboloops': a new microshaped vitreous carbon sample mount for X-ray and neutron crystallography." Acta Crystallographica Section F Structural Biology Communications 70, no. 5 (April 15, 2014): 681–84. http://dx.doi.org/10.1107/s2053230x14005901.

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A novel vitreous carbon mount for macromolecular crystallography, suitable for neutron and X-ray crystallographic studies, has been developed. The technology described here is compatible both with X-ray and neutron cryo-crystallography. The mounts have low density and low background scattering for both neutrons and X-rays. They are prepared by laser cutting, allowing high standards of production quality, the ability to custom-design the mount to specific crystal sizes and large-scale production.
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Dissertations / Theses on the topic "X-ray crystallography"

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Zora, J. A. "X-ray diffraction studies." Thesis, University of Sussex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374467.

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Wall, Clare. "Mathematical methods in protein x-ray crystallography." Thesis, University of York, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403863.

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Mifsud, Richard William. "An exploration of some aspects of molecular replacement in macromolecular crystallography." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/282871.

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This thesis reports work in three areas of X-ray crystallography. An initial chapter describes the structure of a protein, the methods based on the use of X-rays and computer analysis of diffraction patterns to determine crystal structure, and the subsequent derivation of the structure of part or all of a protein molecule. Work to determine the structure of the protein cytokine receptor-like factor 3 (CRLF3) leading to the successful generation of a structural model of a significant part of this molecule is then described in Chapter 2. A variety of techniques had to be deployed to complete this work, and the steps undertaken are described. Analysis was performed principally using phaser, using maximum likelihood methods. Areas for improvement in generating non-crystallographic symmetry (NCS) operators in existing programmes were identified and new and modified algorithms implemented and tested. Searches based on improved single sphere algorithms, and a new two-sphere approach, are reported. These methods showed improvements in many cases and are available for future use. In Chapter 4, work on determining the relative importance of low resolution and high intensity data in molecular replacement solutions is described. This work has shown that high intensity data are more important than the low resolution data, dispelling a common perception and helping in experimental design.
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Meng, Guoyu. "Structural study of levansucrase by x-ray crystallography." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403446.

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Geissbühler, Marc Phillip. "X-ray interfacial crystallography of water on calcite /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/9634.

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Nagpal, Akanksha. "Crystal Structures of Nitroalkane Oxidase: Insights into the Structural Basis for Substrate Specificity and the Catalytic Mechanism." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-07172005-152826/.

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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2006.
Dr. Allen M. Orville, Committee Chair ; Dr. Loren D. Williams, Committee Member ; Dr. Donald F. Doyle, Committee Member ; Dr. Dale E. Edmondson, Committee Member ; Dr. Giovanni Gadda, Committee Member.
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Oblezov, Alexandr Evgenievich. "Crystal structure determination at the Center for X-ray Crystallography a practical guide /." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0002700.

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Collins, Anna. "The X-ray crystallography of Z'>1 materials." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437369.

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Lo, Victor Lai-Xin. "Iterative projection algorithms and applications in x-ray crystallography." Thesis, University of Canterbury. Electrical and Computer Engineering, 2011. http://hdl.handle.net/10092/5476.

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X-ray crystallography is a technique for determining the structure (positions of atoms in space) of molecules. It is a well developed technique, and is applied routinely to both small inorganic and large organic molecules. However, the determination of the structures of large biological molecules by x-ray crystallography can still be an experimentally and computationally expensive task. The data in an x-ray experiment are the amplitudes of the Fourier transform of the electron density in the crystalline specimen. The structure determination problem in x-ray crystallography is therefore identical to a phase retrieval problem in image reconstruction, for which iterative transform algorithms are a common solution method. This thesis is concerned with iterative projection algorithms, a generalized and more powerful version of iterative transform algorithms, and their application to macromolecular x-ray crystallography. A detailed study is made of iterative projection algorithms, including their properties, convergence, and implementations. Two applications to macromolecular crystallography are then investigated. The first concerns reconstruction of binary image and the application of iterative projection algorithms to determining molecular envelopes from x-ray solvent contrast variation data. An effective method for determining molecular envelopes is developed. The second concerns the use of symmetry constraints and the application of iterative projection algorithms to ab initio determination of macromolecular structures from crystal diffraction data. The algorithm is tested on an icosahedral virus and a protein tetramer. The results indicate that ab initio phasing is feasible for structures containing 4-fold or 5-fold non-crystallographic symmetry using these algorithms if an estimate of the molecular envelope is available.
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Alves-Areias, A. "Investigation of host-guest interactions by x-ray crystallography." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395365.

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Books on the topic "X-ray crystallography"

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Rissanen, Kari, ed. Advanced X-Ray Crystallography. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-27407-7.

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Waseda, Yoshio, Eiichiro Matsubara, and Kozo Shinoda. X-Ray Diffraction Crystallography. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-16635-8.

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G, Long Gabrielle, and National Institute of Standards and Technology (U.S.), eds. X-ray topography. Gaithersburg, Md.]: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2004.

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Authier, André. Early days of X-ray crystallography. Oxford: Oxford University Press, 2013.

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Ooi, Li-ling. Principles of x-ray crystallography. Oxford: Oxford University Press, 2010.

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Woolfson, M. M. An introduction to X-ray crystallography. 2nd ed. Cambridge: Cambridge University Press, 1997.

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Authier, André. Dynamical theory of x-ray diffraction. Oxford: Oxford University Press, 2004.

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1934-, Cox David, Vlieg Elias, and Robinson I. K. 1955-, eds. Synchrotron radiation crystallography. London: Academic Press, 1992.

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Crystallography, International Union of. International tables for X-ray crystallography. 2nd ed. Dordrecht: Reidel Pub. Co, 1985.

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Ladd, M. F. C. Structure Determination by X-ray Crystallography. Boston, MA: Springer US, 1993.

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Book chapters on the topic "X-ray crystallography"

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Degtjarik, Oksana, Gabriel Demo, Michaela Wimmerova, and Ivana Kuta Smatanova. "X-Ray Crystallography." In Plant Structural Biology: Hormonal Regulations, 203–21. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-91352-0_11.

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Roth, Lauren E., and F. Akif Tezcan. "X-Ray Crystallography." In Nitrogen Fixation, 147–64. Totowa, NJ: Humana Press, 2011. http://dx.doi.org/10.1007/978-1-61779-194-9_10.

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Ealick, S. E., and C. E. Bugg. "X-Ray Crystallography." In The Bile Acids: Chemistry, Physiology, and Metabolism, 137–65. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-0901-7_4.

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Klostermeier, Dagmar, and Markus G. Rudolph. "X-ray Crystallography." In Biophysical Chemistry, 531–70. Names: Klostermeier, Dagmar, author. | Rudolph, Markus G., author. Title: Biophysical chemistry / Dagmar Klostermeier and Markus G. Rudolph. Description: Boca Raton, FL : CRC Press, Taylor & Francis Group, [2017]: CRC Press, 2018. http://dx.doi.org/10.1201/9781315156910-26.

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McMahon, Malcolm I. "High-Pressure Crystallography." In Advanced X-Ray Crystallography, 69–109. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/128_2011_132.

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Maslen, E. N. "X-ray absorption." In International Tables for Crystallography, 599–608. Chester, England: International Union of Crystallography, 2006. http://dx.doi.org/10.1107/97809553602060000602.

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Arndt, U. W. "X-ray sources." In International Tables for Crystallography, 125–32. Chester, England: International Union of Crystallography, 2006. http://dx.doi.org/10.1107/97809553602060000665.

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Arndt, U. W. "X-ray sources." In International Tables for Crystallography, 159–67. Chester, England: International Union of Crystallography, 2012. http://dx.doi.org/10.1107/97809553602060000818.

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Sanders, D. A. R. "Protein X‐Ray Crystallography." In Handbook of Neurochemistry and Molecular Neurobiology, 456–78. Boston, MA: Springer US, 2007. http://dx.doi.org/10.1007/978-0-387-30401-4_22.

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Ladd, Mark, and Rex Palmer. "X-Rays and X-Ray Diffraction." In Structure Determination by X-ray Crystallography, 111–59. Boston, MA: Springer US, 2012. http://dx.doi.org/10.1007/978-1-4614-3954-7_3.

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Conference papers on the topic "X-ray crystallography"

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Arndt, Ulrich W., and Anne C. Bloomer. "X-ray crystallography with microfocus x-ray sources." In International Symposium on Optical Science and Technology, edited by Carolyn A. MacDonald and Ali M. Khounsary. SPIE, 2000. http://dx.doi.org/10.1117/12.405883.

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Brandão, A. S., and S. L. S. and de Deus de Melo. "INVESTIGATION OF VIRGIN AND RECYCLED ROTOMOLDED POLYETHYLENE USING X-RAY DIFFRACTION AND X-RAY FLUORESCENCE." In International Symposium on Crystallography. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/phypro-sic100-013.

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Altarelli, Massimo. "THE EUROPEAN X-RAY FREE-ELECTRON LASER (XFEL) PROJECT." In International Symposium on Crystallography. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/phypro-sic100-005.

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Johnson, J. E., and Z. Chen. "Virus crystallography using synchrotron X-ray radiation." In X-ray and inner-shell processes. AIP, 1990. http://dx.doi.org/10.1063/1.39824.

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Antonio, S. G., S. T. B. Salvi, D. L. Tita, and C. O. Paiva-Santos. "X-RAY POWDER DIFFRACTION IN THE ACTIVITIES OF THE LABCACC." In International Symposium on Crystallography. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/phypro-sic100-010.

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Muniz, F. T. L. "SIMULATION OF X-RAY POWDER DIFFRACTION PATTERNS USING DYNAMICAL THEORY." In International Symposium on Crystallography. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/phypro-sic100-055.

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Tanaka, J. S., Paiva-Santos C. O., and S. G. Antonio. "JST-DRX: A SOFTWARE TO GENERATE X-RAY POWDER DIFFRACTOGRAMS FROM PATENTS DATA (2q X I)." In International Symposium on Crystallography. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/phypro-sic100-042.

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Owens, Scott M., Johannes B. Ullrich, Igor Y. Ponomarev, D. C. Carter, R. C. Sisk, J. X. Ho, and Walter M. Gibson. "Polycapillary x-ray optics for macromolecular crystallography." In SPIE's 1996 International Symposium on Optical Science, Engineering, and Instrumentation, edited by Richard B. Hoover and F. P. Doty. SPIE, 1996. http://dx.doi.org/10.1117/12.245141.

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Stanton, Martin J., and Walter C. Phillips. "Performance of detectors for x-ray crystallography." In SPIE's 1993 International Symposium on Optics, Imaging, and Instrumentation, edited by Victor J. Orphan. SPIE, 1993. http://dx.doi.org/10.1117/12.164733.

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Phillips, Walter C., Martin J. Stanton, Daniel M. O'Mara, Istvan Naday, and Edwin M. Westbrook. "Modular CCD detector for x-ray crystallography." In IS&T/SPIE's Symposium on Electronic Imaging: Science and Technology, edited by Morley M. Blouke. SPIE, 1993. http://dx.doi.org/10.1117/12.148747.

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Reports on the topic "X-ray crystallography"

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Sax, Martin, and W. Furey. X-ray Crystallography of Botulinum Neurotoxins. Fort Belvoir, VA: Defense Technical Information Center, October 1999. http://dx.doi.org/10.21236/ada374806.

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Sax, Martin, W. Furey, and S. Swaminathan. X-Ray Crystallography of Botulinum Neurotoxins. Fort Belvoir, VA: Defense Technical Information Center, March 2000. http://dx.doi.org/10.21236/ada378753.

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Terwilliger, Thomas C. A brief introduction to x-ray crystallography. Office of Scientific and Technical Information (OSTI), February 2011. http://dx.doi.org/10.2172/1052761.

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Furey, William, Martin Sax, and S. Swaminathan. X-Ray Crystallography of Botulinum Neurotoxin Type E and Its Functional Subunits. Fort Belvoir, VA: Defense Technical Information Center, December 2002. http://dx.doi.org/10.21236/ada413858.

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Rogers, Robin Don, and Gabriela Gurau. Understanding the Interactions of Seawater Ions with Amidoxime through X-Ray Crystallography. Office of Scientific and Technical Information (OSTI), December 2019. http://dx.doi.org/10.2172/1580560.

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Wall, Michael E. Measurement and Interpretation of Diffuse Scattering in X-Ray Diffraction for Macromolecular Crystallography. Office of Scientific and Technical Information (OSTI), October 2017. http://dx.doi.org/10.2172/1400134.

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Sussman, J. L., and I. Silman. Determination By X-Ray Crystallography of the Three Dimensional- Structure of Acetylcholinesterase from Torpedo Electric Organ. Fort Belvoir, VA: Defense Technical Information Center, April 1993. http://dx.doi.org/10.21236/ada274663.

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Sussman, Joel L., and Israel Silman. X-Ray Crystallographic Studies on Acetylcholinesterase and Related Enzymes. Fort Belvoir, VA: Defense Technical Information Center, April 2003. http://dx.doi.org/10.21236/ada416719.

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Nelson, Nathan, and Charles F. Yocum. Structure, Function and Utilization of Plant Photosynthetic Reaction Centers. United States Department of Agriculture, September 2012. http://dx.doi.org/10.32747/2012.7699846.bard.

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Light capturing and energy conversion by PSI is one of the most fundamental processes in nature. In the heart of these adaptations stand PSI, PSII and their light harvesting antenna complexes. The main goal of this grant proposal was to obtain by X-ray crystallography information on the structure of plant photosystem I (PSI) and photosystem II (PSII) supercomplexes. We achieved several milestones along this line but as yet, like several strong laboratories around the world, we have no crystal structure of plant PSII. We have redesigned the purification and crystallization procedures and recently solved the crystal structure of the PSI supercomplex at 3.3 Å resolution. Even though this advance in resolution appears to be relatively small, we obtained a significantly improved model of the supercomplex. The work was published in J. Biol. Chem. (Amunts et al., 2010). The improved electron density map yielded identification and tracing of the PsaK subunit. The location of an additional 10 ß-carotenes, as well as 5 chlorophylls and several loop regions that were previously uninterruptable have been modeled. This represents the most complete plant PSI structure obtained thus far, revealing the locations of and interactions among 17 protein subunits and 193 non-covalently bound photochemical cofactors. We have continued extensive experimental efforts to improve the structure of plant PSI and to obtain PSII preparation amenable to crystallization. Most of our efforts were devoted to obtain well-defined subcomplexes of plant PSII preparations that are amenable to crystallization. We studied the apparent paradox of the high sensitivity of oxygen evolution of isolated thylakoids while BBY particles exhibit remarkable resilience to the same treatment. The integrity of the photosystem II (PSII) extrinsic protein complement as well as calcium effects arise from the Ca2+ atom associated with the site of photosynthetic water oxidation were investigated. This work provides deeper insights into the interaction of PsbO with PSII. Sight-directed mutagenesis indicated the location of critical sites involved in the stability of the water oxidation reaction. When combined with previous results, the data lead to a more detailed model for PsbO binding in eukaryotic PSII.
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Elbaum, Michael, and Peter J. Christie. Type IV Secretion System of Agrobacterium tumefaciens: Components and Structures. United States Department of Agriculture, March 2013. http://dx.doi.org/10.32747/2013.7699848.bard.

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Objectives: The overall goal of the project was to build an ultrastructural model of the Agrobacterium tumefaciens type IV secretion system (T4SS) based on electron microscopy, genetics, and immunolocalization of its components. There were four original aims: Aim 1: Define the contributions of contact-dependent and -independent plant signals to formation of novel morphological changes at the A. tumefaciens polar membrane. Aim 2: Genetic basis for morphological changes at the A. tumefaciens polar membrane. Aim 3: Immuno-localization of VirB proteins Aim 4: Structural definition of the substrate translocation route. There were no major revisions to the aims, and the work focused on the above questions. Background: Agrobacterium presents a unique example of inter-kingdom gene transfer. The process involves cell to cell transfer of both protein and DNA substrates via a contact-dependent mechanism akin to bacterial conjugation. Transfer is mediated by a T4SS. Intensive study of the Agrobacterium T4SS has made it an archetypal model for the genetics and biochemistry. The channel is assembled from eleven protein components encoded on the B operon in the virulence region of the tumor-inducing plasmid, plus an additional coupling protein, VirD4. During the course of our project two structural studies were published presenting X-ray crystallography and three-dimensional reconstruction from electron microscopy of a core complex of the channel assembled in vitro from homologous proteins of E. coli, representing VirB7, VirB9, and VirB10. Another study was published claiming that the secretion channels in Agrobacterium appear on helical arrays around the membrane perimeter and along the entire length of the bacterium. Helical arrangements in bacterial membranes have since fallen from favor however, and that finding was partially retracted in a second publication. Overall, the localization of the T4SS within the bacterial membranes remains enigmatic in the literature, and we believe that our results from this project make a significant advance. Summary of achievements : We found that polar inflations and other membrane disturbances relate to the activation conditions rather than to virulence protein expression. Activation requires low pH and nutrient-poor medium. These stress conditions are also reflected in DNA condensation to varying degrees. Nonetheless, they must be considered in modeling the T4SS as they represent the relevant conditions for its expression and activity. We identified the T4SS core component VirB7 at native expression levels using state of the art super-resolution light microscopy. This marker of the secretion system was found almost exclusively at the cell poles, and typically one pole. Immuno-electron microscopy identified the protein at the inner membrane, rather than at bridges across the inner and outer membranes. This suggests a rare or transient assembly of the secretion-competent channel, or alternatively a two-step secretion involving an intermediate step in the periplasmic space. We followed the expression of the major secreted effector, VirE2. This is a single-stranded DNA binding protein that forms a capsid around the transferred oligonucleotide, adapting the bacterial conjugation to the eukaryotic host. We found that over-expressed VirE2 forms filamentous complexes in the bacterial cytoplasm that could be observed both by conventional fluorescence microscopy and by correlative electron cryo-tomography. Using a non-retentive mutant we observed secretion of VirE2 from bacterial poles. We labeled the secreted substrates in vivo in order detect their secretion and appearance in the plant cells. However the low transfer efficiency and significant background signal have so far hampered this approach.
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