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Stellacyanin
Stellacyanin is a member of the blue or type I copper protein family. This family of copper proteins is generally involved in electron transfer reactions with the Cu center transitioning between the oxidized Cu(II) form and the reduced Cu(I) form. Stellacyanin is ubiquitous among vascular seed plants.Koch M. Velarde M. Harrison MD. Echt S. Fischer M. Messerschmidt A. Dennison C., J. Am. Chem. Soc., 127, 156-166, 2005Online copy/ref> Structure Stellacyanin’s spectroscopic properties help us differentiate it from plastocyanin, which is another monocopper blue protein found in plants. Nersissian Ma, A.M.; Immoos, C.; Hill, M.G.; Hart, P.J.; Williams, G.; Herrmann, R.G.; Valentine, J.S. Uclacyanins, stellacyanins, and plantacyanins are distinct subfamilies of phytocyanins: Plant-specific mononuclear blue copper proteins. Protein Sci. 1998, 7, 1915–1929. It is a 20kDa protein whose structure is made up of beta strands forming two beta sheets to form a Greek key beta barrel wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellacyanin
Stellacyanin is a member of the blue or type I copper protein family. This family of copper proteins is generally involved in electron transfer reactions with the Cu center transitioning between the oxidized Cu(II) form and the reduced Cu(I) form. Stellacyanin is ubiquitous among vascular seed plants.Koch M. Velarde M. Harrison MD. Echt S. Fischer M. Messerschmidt A. Dennison C., J. Am. Chem. Soc., 127, 156-166, 2005Online copy/ref> Structure Stellacyanin’s spectroscopic properties help us differentiate it from plastocyanin, which is another monocopper blue protein found in plants. Nersissian Ma, A.M.; Immoos, C.; Hill, M.G.; Hart, P.J.; Williams, G.; Herrmann, R.G.; Valentine, J.S. Uclacyanins, stellacyanins, and plantacyanins are distinct subfamilies of phytocyanins: Plant-specific mononuclear blue copper proteins. Protein Sci. 1998, 7, 1915–1929. It is a 20kDa protein whose structure is made up of beta strands forming two beta sheets to form a Greek key beta barrel wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Proteins
Copper proteins are proteins that contain one or more copper ions as prosthetic groups. Copper proteins are found in all forms of air-breathing life. These proteins are usually associated with electron-transfer with or without the involvement of oxygen (O2). Some organisms even use copper proteins to carry oxygen instead of iron proteins. A prominent copper proteins in humans is in cytochrome c oxidase (cco). The enzyme cco mediates the controlled combustion that produces Adenosine triphosphate, ATP. Classes The metal centers in the copper proteins can be classified into several types: *Type I copper centres (T1Cu) are characterized by a single copper atom coordinated by two histidine residues and a cysteine residue in a trigonal planar structure, and a variable axial ligand. In Plastocyanin family of copper binding proteins, class I T1Cu proteins (e.g. amicyanin, plastocyanin and pseudoazurin) the axial ligand is the sulfur of methionine, whereas aminoacids other than meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Proteins
Copper proteins are proteins that contain one or more copper ions as prosthetic groups. Copper proteins are found in all forms of air-breathing life. These proteins are usually associated with electron-transfer with or without the involvement of oxygen (O2). Some organisms even use copper proteins to carry oxygen instead of iron proteins. A prominent copper proteins in humans is in cytochrome c oxidase (cco). The enzyme cco mediates the controlled combustion that produces Adenosine triphosphate, ATP. Classes The metal centers in the copper proteins can be classified into several types: *Type I copper centres (T1Cu) are characterized by a single copper atom coordinated by two histidine residues and a cysteine residue in a trigonal planar structure, and a variable axial ligand. In Plastocyanin family of copper binding proteins, class I T1Cu proteins (e.g. amicyanin, plastocyanin and pseudoazurin) the axial ligand is the sulfur of methionine, whereas aminoacids other than meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutamine
Glutamine (symbol Gln or Q) is an α-amino acid that is used in the biosynthesis of proteins. Its side chain is similar to that of glutamic acid, except the carboxylic acid group is replaced by an amide. It is classified as a charge-neutral, polar amino acid. It is non-essential and conditionally essential in humans, meaning the body can usually synthesize sufficient amounts of it, but in some instances of stress, the body's demand for glutamine increases, and glutamine must be obtained from the diet. It is encoded by the codons CAA and CAG. In human blood, glutamine is the most abundant free amino acid. The dietary sources of glutamine include especially the protein-rich foods like beef, chicken, fish, dairy products, eggs, vegetables like beans, beets, cabbage, spinach, carrots, parsley, vegetable juices and also in wheat, papaya, Brussels sprouts, celery, kale and fermented foods like miso. Functions Glutamine plays a role in a variety of biochemical functions: * Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lignin
Lignin is a class of complex organic polymers that form key structural materials in the support tissues of most plants. Lignins are particularly important in the formation of cell walls, especially in wood and bark, because they lend rigidity and do not rot easily. Chemically, lignins are polymers made by cross-linking phenolic precursors. History Lignin was first mentioned in 1813 by the Swiss botanist A. P. de Candolle, who described it as a fibrous, tasteless material, insoluble in water and alcohol but soluble in weak alkaline solutions, and which can be precipitated from solution using acid. He named the substance “lignine”, which is derived from the Latin word '' lignum'', meaning wood. It is one of the most abundant organic polymers on Earth, exceeded only by cellulose. Lignin constitutes 30% of non-fossil organic carbon on Earth, and 20 to 35% of the dry mass of wood. Lignin is present in red algae, which suggest that the common ancestor of plants and red algae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymerase Chain Reaction
The polymerase chain reaction (PCR) is a method widely used to rapidly make millions to billions of copies (complete or partial) of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it (or a part of it) to a large enough amount to study in detail. PCR was invented in 1983 by the American biochemist Kary Mullis at Cetus Corporation; Mullis and biochemist Michael Smith (chemist), Michael Smith, who had developed other essential ways of manipulating DNA, were jointly awarded the Nobel Prize in Chemistry in 1993. PCR is fundamental to many of the procedures used in genetic testing and research, including analysis of Ancient DNA, ancient samples of DNA and identification of infectious agents. Using PCR, copies of very small amounts of DNA sequences are exponentially amplified in a series of cycles of temperature changes. PCR is now a common and often indispensable technique used in medical laboratory research for a broad variety of applications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methionine
Methionine (symbol Met or M) () is an essential amino acid in humans. As the precursor of other amino acids such as cysteine and taurine, versatile compounds such as SAM-e, and the important antioxidant glutathione, methionine plays a critical role in the metabolism and health of many species, including humans. It is encoded by the codon AUG. Methionine is also an important part of angiogenesis, the growth of new blood vessels. Supplementation may benefit those suffering from copper poisoning. Overconsumption of methionine, the methyl group donor in DNA methylation, is related to cancer growth in a number of studies. Methionine was first isolated in 1921 by John Howard Mueller. Biochemical details Methionine (abbreviated as Met or M; encoded by the codon AUG) is an α-amino acid that is used in the biosynthesis of proteins. It contains a carboxyl group (which is in the deprotonated −COO− form under biological pH conditions), an amino group (which is in the protonated fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reduction Potential
Redox potential (also known as oxidation / reduction potential, ''ORP'', ''pe'', ''E_'', or E_) is a measure of the tendency of a chemical species to acquire electrons from or lose electrons to an electrode and thereby be reduced or oxidised respectively. Redox potential is expressed in volts (V). Each species has its own intrinsic redox potential; for example, the more positive the reduction potential (reduction potential is more often used due to general formalism in electrochemistry), the greater the species' affinity for electrons and tendency to be reduced. Measurement and interpretation In aqueous solutions, redox potential is a measure of the tendency of the solution to either gain or lose electrons when it is subjected to change by introduction of a new species. A solution with a higher (more positive) reduction potential than the new species will have a tendency to gain electrons from the new species (i.e. to be reduced by oxidizing the new species) and a solution with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycoprotein
Glycoproteins are proteins which contain oligosaccharide chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glycosylation. Secreted extracellular proteins are often glycosylated. In proteins that have segments extending extracellularly, the extracellular segments are also often glycosylated. Glycoproteins are also often important integral membrane proteins, where they play a role in cell–cell interactions. It is important to distinguish endoplasmic reticulum-based glycosylation of the secretory system from reversible cytosolic-nuclear glycosylation. Glycoproteins of the cytosol and nucleus can be modified through the reversible addition of a single GlcNAc residue that is considered reciprocal to phosphorylation and the functions of these are likely to be an additional regulatory mechanism that controls phosphorylation-based signalling. In contrast, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Transfer
Electron transfer (ET) occurs when an electron relocates from an atom or molecule to another such chemical entity. ET is a mechanistic description of certain kinds of redox reactions involving transfer of electrons. Electrochemical processes are ET reaction. ET reactions are relevant to photosynthesis and respiration. ET reactions commonly involve transition metal complexes, In organic chemistry ET is a step in some commercial polymerization reactions. It is foundational to photoredox catalysis. Classes of electron transfer Inner-sphere electron transfer In inner-sphere ET, the two redox centers are covalently linked during the ET. This bridge can be permanent, in which case the electron transfer event is termed intramolecular electron transfer. More commonly, however, the covalent linkage is transitory, forming just prior to the ET and then disconnecting following the ET event. In such cases, the electron transfer is termed intermolecular electron transfer. A famous exa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histidine
Histidine (symbol His or H) is an essential amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated –NH3+ form under biological conditions), a carboxylic acid group (which is in the deprotonated –COO− form under biological conditions), and an imidazole side chain (which is partially protonated), classifying it as a positively charged amino acid at physiological pH. Initially thought essential only for infants, it has now been shown in longer-term studies to be essential for adults also. It is encoded by the codons CAU and CAC. Histidine was first isolated by Albrecht Kossel and Sven Gustaf Hedin in 1896. It is also a precursor to histamine, a vital inflammatory agent in immune responses. The acyl radical is histidyl. Properties of the imidazole side chain The conjugate acid (protonated form) of the imidazole side chain in histidine has a p''K''a of approximately 6.0. Thus, below a pH of 6, the imidazole ring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter waves and acoustic waves can also be considered forms of radiative energy, and recently gravitational waves have been associated with a spectral signature in the context of the Laser Interferometer Gravitational-Wave Observatory (LIGO) In simpler terms, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Historically, spectroscopy originated as the study of the wavelength dependence of the absorption by gas phase matter of visible light dispersed by a prism. Spectroscopy, primarily in the electromagnetic spectrum, is a fundamental exploratory tool in the fields of astronomy, chemistry, materials science, and physics, allowing the composition, physical structure and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
