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Crystallography, X-Ray: The study of crystal structure using X-Ray diffraction techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

Using X-ray Crystallography, Biophysics, and Functional Assays to Determine the Mechanisms Governing T-cell Receptor Recognition of Cancer Antigens

1Division of Infection and Immunity and Systems Immunity Research Institute, Cardiff University, 2Department of Oncology, University Hospital of Lausanne (CHUV), 3Ludwig Insitutue for Cancer Research, Lausanne Branch, University of Lausanne

JoVE 54991

 Immunology and Infection

Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene

1ARC Centre of Excellence in Advanced Molecular Imaging, School of Physics, University of Melbourne, 2Australian Research Council (ARC) Centre of Excellence in Advanced Molecular Imaging, Department of Chemistry and Physics, La Trobe Institute for Molecular Sciences, La Trobe University, 3Department of Physics, Imperial College London, 4Florey Institute of Neuroscience and Mental Health, 5Science and Engineering Faculty, Queensland University of Technology, 6Swinburne University of Technology, 7Department of Engineering Science, University of Oxford, 8Brookhaven National Laboratory, 9Linac Coherent Light Source, SLAC National Accelerator Laboratory, 10BioXFEL Science and Technology Center, 11Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, 12Australian Synchrotron

JoVE 56296


Growing Crystals for X-ray Diffraction Analysis

JoVE 10216

Source: Laboratory of Dr. Jimmy Franco - Merrimack College

X-ray crystallography is a method commonly used to determine the spatial arrangement of atoms in a crystalline solid, which allows for the determination of the three-dimensional shape of a molecule or complex. Determining the three-dimensional structure of a compound is of particular importance, since a compound's structure and function are intimately related. Information about a compound's structure is often used to explain its behavior or reactivity. This is one of the most useful techniques for solving the three-dimensional structure of a compound or complex, and in some cases it may be the only viable method for determining the structure. Growing X-ray quality crystals is the key component of X-ray crystallography. The size and quality of the crystal is often highly dependent on the composition of the compound being examined by X-ray crystallography. Typically compounds containing heavier atoms produce a greater diffraction pattern, thus require smaller crystals. Generally, single crystals with well-defined faces are optimal, and typically for organic compounds, the crystals need to be larger than those containing heavy atoms. Without viable crystals, X-ray crystallography is not feasible. Some molecules are inherently more crystalline than others, thu

 Organic Chemistry

From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins

1Department of Biological Sciences, Markey Center for Structural Biology, Purdue University, 2National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health, 3National Institute of General Medical Sciences (NIGMS), National Institutes of Health

JoVE 53245


Single Crystal and Powder X-ray Diffraction

JoVE 10462

Source: Tamara M. Powers, Department of Chemistry, Texas A&M University 

X-ray crystallography is a technique that uses X-rays to study the structure of molecules. X-ray diffraction (XRD) experiments are routinely carried out with either single-crystal or powdered samples.

Single-crystal XRD: Single-crystal XRD allows for absolute structure determination. With single-crystal XRD data, the exact atomic positions can be observed, and thus bond lengths and angles can be determined. This technique provides the structure within a single crystal, which does not necessarily represent the bulk of the material. Therefore, additional bulk characterization methods must be utilized to prove the identity and purity of a compound. Powder XRD: Unlike single-crystal XRD, powder XRD looks at a large sample of polycrystalline material and therefore is considered a bulk characterization technique. The powder pattern is considered a "fingerprint" for a given material; it provides information about the phase (polymorph) and crystallinity of the material. Typically, powder XRD is used to study minerals, zeolites, metal-organic frameworks (MOFs), and other extended solids. P

 Inorganic Chemistry

Quadruply Metal-Metal Bonded Paddlewheels

JoVE 10441

Source: Corey Burns, Tamara M. Powers, Department of Chemistry, Texas A&M University

Paddlewheel complexes are a class of compounds comprised of two metal ions (1st, 2nd, or 3rd row transition metals) held in proximity by four bridging ligands (most commonly formamidinates or carboxylates) (Figure 1). Varying the identity of the metal ion and the bridging ligand provides access to large families of paddlewheel complexes. The structure of paddlewheel complexes allows for metal-metal bonding, which plays a vital role in the structure and reactivity of these complexes. Due to the diversity of electronic structures that are available to paddlewheel complexes - and the corresponding differences in M-M bonding displayed by these structures - paddlewheel complexes have found application in diverse areas, such as in homogeneous catalysis and as building blocks for metal-organic frameworks (MOFs). Understanding the electronic structure of the M-M bonds in paddlewheel complexes is critical to understanding their structures and thus to application of these complexes in coordination chemistry and catalysis. Figure 1. General structure of paddlewheel complexes, wh

 Inorganic Chemistry

Purifying Compounds by Recrystallization

JoVE 10184

Source: Laboratory of Dr. Jimmy Franco - Merrimack College

Recrystallization is a technique used to purify solid compounds.1 Solids tend to be more soluble in hot liquids than in cold liquids. During recrystallization, an impure solid compound is dissolved in a hot liquid until the solution is saturated, and then the liquid is allowed to cool.2 The compound should then form relatively pure crystals. Ideally, any impurities that are present will remain in the solution and will not be incorporated into the growing crystals (Figure 1). The crystals can then be removed from the solution by filtration. Not all of the compound is recoverable — some will remain in the solution and will be lost. Recrystallization is not generally thought of as a separation technique; rather, it is a purification technique in which a small amount of an impurity is removed from a compound. However, if the solubility properties of two compounds are sufficiently different, recrystallization can be used to separate them, even if they are present in nearly equal amounts. Recrystallization works best when most impurities have already been removed by another method, such as extraction or column chromatography. Fi</span>…		</p>
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Multi-target Parallel Processing Approach for Gene-to-structure Determination of the Influenza Polymerase PB2 Subunit

1Protein Crystallization Lab, Emerald Bio, 2Molecular Biology Lab, Emerald Bio, 3Scientific Sales Representative, Emerald Bio, 4Group Leader II, Emerald Bio, 5Group Leader I, Emerald Bio, 6Chair of Advisory Board, Emerald Bio, 7Director of Multi-Target Services, Emerald Bio, 8Senior Project Leader, Emerald Bio, 9Project Leader II & SSGCID Site Manager, Emerald Bio

JoVE 4225

 Immunology and Infection

Generation of Escape Variants of Neutralizing Influenza Virus Monoclonal Antibodies

1Department of Microbiology, Icahn School of Medicine at Mount Sinai, 2Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, 3The Department of Medicine, Section of Rheumatology, The Knapp Center for Lupus and Immunology Research, The University of Chicago

JoVE 56067

 Immunology and Infection

In Situ Neutron Powder Diffraction Using Custom-made Lithium-ion Batteries

1School of Chemistry, University of Sydney, 2Institute for Superconducting & Electronic Materials, University of Wollongong, 3Australian Synchrotron, 4Australian Nuclear Science and Technology Organisation, 5School of Mechanical, Materials, and Mechatronic Engineering, University of Wollongong, 6School of Chemistry, University of New South Wales

JoVE 52284


Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers

1School of Physics and Astronomy, University of Leeds, 2Institute of Materials Research, University of Leeds, 3School of Chemistry, University of Edinburgh, 4Department of Chemical Engineering, Northeastern University, 5Department of Physics, Northeastern University

JoVE 50603


Efficient Mammalian Cell Expression and Single-step Purification of Extracellular Glycoproteins for Crystallization

1Molecular Microbiology and Microbial Pathogenesis Program, Washington University School of Medicine, 2Department of Internal Medicine, Washington University School of Medicine, 3Drug Discovery Program in Pulmonary and Critical Care Medicine, Washington University School of Medicine, 4Biochemistry Program, Washington University School of Medicine, 5Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, 6Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, 7Department of Cell Biology and Physiology, Washington University School of Medicine

JoVE 53445


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