 | |
| Content | |
|---|---|
| Description | circular dichroism spectral and metadata. |
| Contact | |
| Research center | Birkbeck College, University of London |
| Laboratory | Department of Crystallography, Institute of Structural and Molecular Biology |
| Authors | B A Wallace |
| Primary citation | Whitmore & al. (2011) [1] |
| Release date | 2010 |
| Access | |
| Website | pcddb |
The Protein Circular Dichroism Data Bank (PCDDB) is a database of circular dichroism and synchrotron radiation. [1]
Circular dichroism (CD) is dichroism involving circularly polarized light, i.e., the differential absorption of left- and right-handed light. Left-hand circular (LHC) and right-hand circular (RHC) polarized light represent two possible spin angular momentum states for a photon, and so circular dichroism is also referred to as dichroism for spin angular momentum. This phenomenon was discovered by Jean-Baptiste Biot, Augustin Fresnel, and Aimé Cotton in the first half of the 19th century. Circular dichroism and circular birefringence are manifestations of optical activity. It is exhibited in the absorption bands of optically active chiral molecules. CD spectroscopy has a wide range of applications in many different fields. Most notably, UV CD is used to investigate the secondary structure of proteins. UV/Vis CD is used to investigate charge-transfer transitions. Near-infrared CD is used to investigate geometric and electronic structure by probing metal d→d transitions. Vibrational circular dichroism, which uses light from the infrared energy region, is used for structural studies of small organic molecules, and most recently proteins and DNA.
Synchrotron radiation is the electromagnetic radiation emitted when relativistic charged particles are subject to an acceleration perpendicular to their velocity. It is produced artificially in some types of particle accelerators or naturally by fast electrons moving through magnetic fields. The radiation produced in this way has a characteristic polarization, and the frequencies generated can range over a large portion of the electromagnetic spectrum.
A synchrotron light source is a source of electromagnetic radiation (EM) usually produced by a storage ring, for scientific and technical purposes. First observed in synchrotrons, synchrotron light is now produced by storage rings and other specialized particle accelerators, typically accelerating electrons. Once the high-energy electron beam has been generated, it is directed into auxiliary components such as bending magnets and insertion devices in storage rings and free electron lasers. These supply the strong magnetic fields perpendicular to the beam that are needed to stimulate the high energy electrons to emit photons.
Diamond Light Source is the UK's national synchrotron light source science facility located at the Harwell Science and Innovation Campus in Oxfordshire.
A synchrotron is a particular type of cyclic particle accelerator, descended from the cyclotron, in which the accelerating particle beam travels around a fixed closed-loop path. The magnetic field which bends the particle beam into its closed path increases with time during the accelerating process, being synchronized to the increasing kinetic energy of the particles.
SPring-8 is a synchrotron radiation facility located in Sayo Town, Sayo District, Hyōgo Prefecture, Japan, which is the main facility of Harima Science Garden City. It was developed jointly by RIKEN and the Japan Atomic Energy Research Institute, and is owned and managed by RIKEN, and run under commission by the Japan Synchrotron Radiation Research Institute. The machine consists of a storage ring containing an 8 GeV electron beam. On its path around the storage ring, the beam passes through insertion devices to produce synchrotron radiation with energies ranging from soft X-rays up to hard X-rays. The synchrotron radiation produced at SPring-8 is used for materials analysis and biochemical protein characterization by many Japanese manufacturers and universities.
The Australian Synchrotron is a 3 GeV national synchrotron radiation facility located in Clayton, in the south-eastern suburbs of Melbourne, Victoria. The facility opened in 2007, and is operated by the Australian Nuclear Science and Technology Organisation.
Vibrational circular dichroism (VCD) is a spectroscopic technique which detects differences in attenuation of left and right circularly polarized light passing through a sample. It is the extension of circular dichroism spectroscopy into the infrared and near infrared ranges.
The Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung m. b. H., abbreviated BESSY, is a research establishment in the Adlershof district of Berlin. Founded on 5 March 1979, it currently operates one of Germany's 3rd generation synchrotron radiation facilities, BESSY II. Originally part of the Leibniz Association, BESSY now belongs to the Helmholtz-Zentrum Berlin.
A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies to contain them in well-defined beams. Large accelerators are used for fundamental research in particle physics. Accelerators are also used as synchrotron light sources for the study of condensed matter physics. Smaller particle accelerators are used in a wide variety of applications, including particle therapy for oncological purposes, radioisotope production for medical diagnostics, ion implanters for the manufacture of semiconductors, and accelerator mass spectrometers for measurements of rare isotopes such as radiocarbon.
Cryo bio-crystallography is the application of crystallography to biological macromolecules at cryogenic temperatures.
ANKA is a synchrotron light source facility at the Karlsruhe Institute of Technology (KIT) in Karlsruhe, Germany. The KIT runs ANKA as a national synchrotron light source and as a large scale user facility for the international science community. Being a large scale machine of the performance category LK II of the Helmholtz Association, ANKA is part of a national and European infrastructure offering research services to scientific and commercial users for their purposes in research and development. The facility was opened to external users in 2003.
Alison Rodger FRSC FRACI FAA CChem is a professor of chemistry at Macquarie University. Her research considers biomacromolecular structures and their characterisation. She is currently developing Raman Linear Difference Spectroscopy and fluorescence detected liner dichroism to understand biomacromolecular structure and interactions with application to the division of bacterial cells.
Lieselotte Templeton was a German-born American crystallographer. She received the Patterson Award of the American Crystallographic Association together with her husband David H. Templeton in 1987.
SOLARIS is a synchrotron light source in the city of Kraków in Poland. It is the only one facility of its kind in Central-Eastern Europe. Built in 2015, under the auspices of the Jagiellonian University, it is located on the Campus of the 600th Anniversary of the Jagiellonian University Revival, in the southern part of the city. It is the central facility of the National Synchrotron Radiation Centre SOLARIS.
Hyper–Rayleigh scattering optical activity, a form of chiroptical harmonic scattering, is a nonlinear optical physical effect whereby chiral scatterers convert light to higher frequencies via harmonic generation processes, in a way that the intensity of generated light depends on the chirality of the scatterers. "Hyper–Rayleigh scattering" is a nonlinear optical counterpart to Rayleigh scattering. "Optical activity" refers to any changes in light properties that are due to chirality.
Sakura Pascarelli is an Italian physicist and the scientific director at the European XFEL. Her research focuses on the study on matter at extreme conditions of pressure, temperature and magnetic fields, in particular using X-ray absorption spectroscopy (XAS) and X-ray Magnetic Linear and Circular Dichroism (XMCD).
John R. Helliwell is a British crystallographer known for his pioneering work in the use of synchrotron radiation in macromolecular crystallography.
Bonnie Ann Wallace, FRSC is a British and American biophysicist and biochemist. She is a professor of molecular biophysics in the department of biological sciences, formerly the department of crystallography, at Birkbeck College, University of London, U.K.
Synchrotron radiation circular dichroism spectroscopy, commonly referred to as SRCD and also known as VUV-circular dichroism or VUVCD spectroscopy, is a powerful extension to the technique of circular dichroism (CD) spectroscopy, often used to study structural properties of biological molecules such as proteins and nucleic acids. The physical principles of SRCD are essentially identical to those of CD, in that the technique measures the difference in absorption (ΔA) of left (AL) and right (AR) circularly polarized light (ΔA=AL-AR) by a sample in solution. To obtain a CD(SRCD) spectrum the sample must be innately optically active (chiral), or, in some way be induced to have chiral properties, as only then will there be an observable difference in absorption of the left and right circularly polarized light. The major advantages of SRCD over CD arise from the ability to measure data over an extended wavelength range into the vacuum ultra violet (VUV) end of the spectrum. As these measurements are utilizing a light source with a higher photon flux than a bench-top CD machine it means data are more accurate at these extended wavelengths because there is a larger signal over the background noise and, generally, less sample is needed when recording the spectra and there is more information content available in the data. Many beamlines now exist around the world to enable the measurement of SRCD data.
 | This Biological database-related article is a stub. You can help Wikipedia by expanding it. |