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List Of Biophysically Important Macromolecular Crystal Structures
Crystal structures of protein and nucleic acid molecules and their complexes are central to the practice of most parts of biophysics, and have shaped much of what we understand scientifically at the atomic-detail level of biology. Their importance is underlined by the United Nations declaring 2014 as the International Year of Crystallography, as the 100th anniversary of Max von Laue's 1914 Nobel prize for discovering the diffraction of X-rays by crystals. This chronological list of biophysically notable protein and nucleic acid structures is loosely based on a review in the ''Biophysical Journal''. The list includes all the first dozen distinct structures, those that broke new ground in subject or method, and those that became model systems for work in future biophysical areas of research. Myoglobin 1960 - Myoglobin was the very first high-resolution crystal structure of a protein molecule. Myoglobin cradles an iron-containing heme group that reversibly binds oxygen for use in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin Beta Red WhBkg
Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocytes) of almost all vertebrates (the exception being the fish family Channichthyidae) as well as the tissues of some invertebrates. Hemoglobin in blood carries oxygen from the respiratory organs (''e.g.'' lungs or gills) to the rest of the body (''i.e.'' tissues). There it releases the oxygen to permit aerobic respiration to provide energy to power functions of an organism in the process called metabolism. A healthy individual human has 12to 20grams of hemoglobin in every 100mL of blood. In mammals, the chromoprotein makes up about 96% of the red blood cells' dry content (by weight), and around 35% of the total content (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL O2 per gram, which increases the total blood oxygen ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Sheet
The beta sheet, (β-sheet) (also β-pleated sheet) is a common motif of the regular protein secondary structure. Beta sheets consist of beta strands (β-strands) connected laterally by at least two or three backbone hydrogen bonds, forming a generally twisted, pleated sheet. A β-strand is a stretch of polypeptide chain typically 3 to 10 amino acids long with backbone in an extended conformation. The supramolecular association of β-sheets has been implicated in the formation of the fibrils and protein aggregates observed in amyloidosis, notably Alzheimer's disease. History The first β-sheet structure was proposed by William Astbury in the 1930s. He proposed the idea of hydrogen bonding between the peptide bonds of parallel or antiparallel extended β-strands. However, Astbury did not have the necessary data on the bond geometry of the amino acids in order to build accurate models, especially since he did not then know that the peptide bond was planar. A refined versi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbohydrates
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or may not be different from ''n''), which does not mean the H has covalent bonds with O (for example with , H has a covalent bond with C but not with O). However, not all carbohydrates conform to this precise stoichiometric definition (e.g., uronic acids, deoxy-sugars such as fucose), nor are all chemicals that do conform to this definition automatically classified as carbohydrates (e.g. formaldehyde and acetic acid). The term is most common in biochemistry, where it is a synonym of saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. Monosaccharides and disaccharides, the smallest (lower molecular weight) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysozyme
Lysozyme (EC 3.2.1.17, muramidase, ''N''-acetylmuramide glycanhydrolase; systematic name peptidoglycan ''N''-acetylmuramoylhydrolase) is an antimicrobial enzyme produced by animals that forms part of the innate immune system. It is a glycoside hydrolase that catalyzes the following process: : Hydrolysis of (1→4)-β-linkages between ''N''-acetylmuramic acid and ''N''-acetyl-D-glucosamine residues in a peptidoglycan and between ''N''-acetyl-D-glucosamine residues in chitodextrins Peptidoglycan is the major component of gram-positive bacterial cell wall. This hydrolysis in turn compromises the integrity of bacterial cell walls causing lysis of the bacteria. Lysozyme is abundant in secretions including tears, saliva, human milk, and mucus. It is also present in cytoplasmic granules of the macrophages and the polymorphonuclear neutrophils (PMNs). Large amounts of lysozyme can be found in egg white. C-type lysozymes are closely related to α-lactalbumin in sequence and structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HEW Lysozyme Rib Bw
Hew is a masculine given name. Notable people with the name include: * Hew Ainslie (1792–1878), Scottish poet * Hew Dalrymple, Lord North Berwick (1652–1737), Scottish judge and politician * Sir Hew Dalrymple, 2nd Baronet (1712-1790), Scottish politician, grandson of the above * Hew Dalrymple (advocate) (c. 1740–1774), Scottish advocate, poet and Attorney-General of Grenada * Sir Hew Dalrymple, 3rd Baronet (1746–1800), Scottish politician, son of the 2nd Baronet * Sir Hew Dalrymple, 1st Baronet, of High Mark (1750–1830), British Army general * Hew Hamilton Dalrymple (1857–1945), Scottish politician * Hew Dalrymple Fanshawe (1860-1957), British Army First World War general * Hew Fraser (1877-1938), British field hockey player and politician * Hew Raymond Griffiths (born 1962), a ring leader of DrinkOrDie or DOD, an underground software piracy network * Sir Hew Dalrymple-Hamilton, 4th Baronet (1774–1834), British politician * Sir Hew Hamilton-Dalrymple, 10th Baronet ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphyrin
Porphyrins ( ) are a group of heterocyclic macrocycle organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (=CH−). The parent of porphyrin is porphine, a rare chemical compound of exclusively theoretical interest. Substituted porphines are called porphyrins. With a total of 26 π-electrons, of which 18 π-electrons form a planar, continuous cycle, the porphyrin ring structure is often described as aromatic. One result of the large conjugated system is that porphyrins typically absorb strongly in the visible region of the electromagnetic spectrum, i.e. they are deeply colored. The name "porphyrin" derives from the Greek word πορφύρα (''porphyra''), meaning ''purple''. Complexes of porphyrins Concomitant with the displacement of two N-''H'' protons, porphyrins bind metal ions in the N4 "pocket". The metal ion usually has a charge of 2+ or 3+. A schematic equation for these syntheses is shown: :H2porp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soret Peak
In spectroscopy, a Soret peak or Soret band is an intense peak in the blue wavelength region of the visible spectrum. The peak is named after its discoverer, Jacques-Louis Soret. The term is commonly used in absorption spectroscopy, corresponding to a wavelength of maximum absorption (electromagnetic radiation) ranging around 400 nm in the blue region. Examples The Soret band arises primarily due to an electron dipole movement that allows π-π* transitions; most common in porphyrin compounds. Most analytical studies of porphyrincontaining moiety can be done using ultraviolet–visible spectroscopy and exciting wavelength at the respective Soret band wavelength. For example, the "Soret peak" is used to describe the absorption of vividly-pigmented heme-containing moieties, such as various cytochromes. For example, the cytochromes P450, a diverse class of monooxygenase enzymes, exhibit a Soret peak at 450 nm in their reduced form when saturated with carbon monoxide. This i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleochroism
Pleochroism (from Greek πλέων, ''pléōn'', "more" and χρῶμα, ''khrôma'', "color") is an optical phenomenon in which a substance has different colors when observed at different angles, especially with polarized light. Background Anisotropic crystals will have optical properties that vary with the direction of light. The direction of the electric field determines the polarization of light, and crystals will respond in different ways if this angle is changed. These kinds of crystals have one or two optical axes. If absorption of light varies with the angle relative to the optical axis in a crystal then pleochroism results. Anisotropic crystals have double refraction of light where light of different polarizations is bent different amounts by the crystal, and therefore follows different paths through the crystal. The components of a divided light beam follow different paths within the mineral and travel at different speeds. When the mineral is observed at some a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Perutz
Max Ferdinand Perutz (19 May 1914 – 6 February 2002) was an Austrian-born British molecular biologist, who shared the 1962 Nobel Prize for Chemistry with John Kendrew, for their studies of the structures of haemoglobin and myoglobin. He went on to win the Royal Medal of the Royal Society in 1971 and the Copley Medal in 1979. At Cambridge he founded and chaired (1962–79) The Medical Research Council (MRC) Laboratory of Molecular Biology (LMB), fourteen of whose scientists have won Nobel Prizes. Perutz's contributions to molecular biology in Cambridge are documented in ''The History of the University of Cambridge: Volume 4 (1870 to 1990)'' published by the Cambridge University Press in 1992. Early life and education Perutz was born in Vienna, the son of Adele "Dely" (Goldschmidt) and Hugo Perutz, a textile manufacturer. His parents were Jewish by ancestry, but had baptised Perutz in the Catholic religion. Although Perutz rejected religion and was an atheist in his later year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,3-Bisphosphoglycerate
2,3-Bisphosphoglyceric acid (conjugate base 2,3-bisphosphoglycerate) (2,3-BPG), also known as 2,3-diphosphoglyceric acid (conjugate base 2,3-diphosphoglycerate) (2,3-DPG), is a three-carbon isomer of the glycolytic intermediate 1,3-bisphosphoglyceric acid (1,3-BPG). -2,3-BPG is present in human red blood cells (RBC; erythrocyte) at approximately 5 mmol/L. It binds with greater affinity to deoxygenated hemoglobin (e.g., when the red blood cell is near respiring tissue) than it does to oxygenated hemoglobin (e.g., in the lungs) due to conformational differences: 2,3-BPG (with an estimated size of about 9 Å) fits in the deoxygenated hemoglobin conformation (with an 11-Angstrom pocket), but not as well in the oxygenated conformation (5 Angstroms). It interacts with deoxygenated hemoglobin beta subunits and decreases the affinity for oxygen and allosterically promotes the release of the remaining oxygen molecules bound to the hemoglobin. Therefore, it enhances the ability of RBC ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allostery
In biochemistry, allosteric regulation (or allosteric control) is the regulation of an enzyme by binding an effector molecule at a site other than the enzyme's active site. The site to which the effector binds is termed the ''allosteric site'' or ''regulatory site''. Allosteric sites allow effectors to bind to the protein, often resulting in a conformational change and/or a change in protein dynamics. Effectors that enhance the protein's activity are referred to as ''allosteric activators'', whereas those that decrease the protein's activity are called ''allosteric inhibitors''. Allosteric regulations are a natural example of control loops, such as feedback from downstream products or feedforward from upstream substrates. Long-range allostery is especially important in cell signaling. Allosteric regulation is also particularly important in the cell's ability to adjust enzyme activity. The term ''allostery'' comes from the Ancient Greek ''allos'' (), "other", and ''stereos' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
