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Glyceric Acid
Glyceric acid is a natural three-carbon sugar acid obtained from the oxidation of glycerol. CH2OH-CHOH-CH2OH+O2→CH2OH-CHOH-COOH+H2O Salts and esters of glyceric acid are known as glycerates. Biochemistry Several phosphate derivatives of glyceric acid, including 2-phosphoglyceric acid, 3-phosphoglyceric acid, 2,3-bisphosphoglyceric acid, and 1,3-bisphosphoglyceric acid, are important biochemical intermediates in glycolysis. 3-phosphoglyceric acid is an important molecule for the biosynthesis of the amino acid serine, which in turn can be used in the synthesis of glycine Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid ( carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinog ... and cysteine. References 2. J.Berg,J.L.Tymoczko,L.Stryer. Biochemistry,7th edition. Sugar acids Alpha hydroxy acids Vicinal diols Propionic acids [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,3-bisphosphoglyceric Acid
1,3-Bisphosphoglyceric acid (1,3-Bisphosphoglycerate or 1,3BPG) is a 3-carbon organic molecule present in most, if not all, living organisms. It primarily exists as a metabolic intermediate in both glycolysis during respiration and the Calvin cycle during photosynthesis. 1,3BPG is a transitional stage between glycerate 3-phosphate and glyceraldehyde 3-phosphate during the fixation/reduction of CO2. 1,3BPG is also a precursor to 2,3-bisphosphoglycerate which in turn is a reaction intermediate in the glycolytic pathway. Biological structure and role 1,3-Bisphosphoglycerate is the conjugate base of 1,3-bisphosphoglyceric acid. It is phosphorylated at the number 1 and 3 carbons. The result of this phosphorylation gives 1,3BPG important biological properties such as the ability to phosphorylate ADP to form the energy storage molecule ATP. In glycolysis As previously mentioned 1,3BPG is a metabolic intermediate in the glycolytic pathway. It is created by the exergonic oxidati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3-phosphoglyceric Acid
3-Phosphoglyceric acid (3PG, 3-PGA, or PGA) is the conjugate acid of 3-phosphoglycerate or glycerate 3-phosphate (GP or G3P). This glycerate is a biochemically significant metabolic intermediate in both glycolysis and the Calvin-Benson cycle. The anion is often termed as PGA when referring to the Calvin-Benson cycle. In the Calvin-Benson cycle, 3-phosphoglycerate is typically the product of the spontaneous scission of an unstable 6-carbon intermediate formed upon CO2 fixation. Thus, two equivalents of 3-phosphoglycerate are produced for each molecule of CO2 that is fixed. In glycolysis, 3-phosphoglycerate is an intermediate following the dephosphorylation ( reduction) of 1,3-bisphosphoglycerate. Glycolysis In the glycolytic pathway, 1,3-bisphosphoglycerate is dephosphorylated to form 3-phosphoglyceric acid in a coupled reaction producing two ATP via substrate-level phosphorylation. The single phosphate group left on the 3-PGA molecule then moves from an end carbon to a central ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycolysis
Glycolysis is the metabolic pathway that converts glucose () into pyruvate (). The free energy released in this process is used to form the high-energy molecules adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide (NADH). Glycolysis is a sequence of ten reactions catalyzed by enzymes. Glycolysis is a metabolic pathway that does not require oxygen (In anaerobic conditions pyruvate is converted to lactic acid). The wide occurrence of glycolysis in other species indicates that it is an ancient metabolic pathway. Indeed, the reactions that make up glycolysis and its parallel pathway, the pentose phosphate pathway, occur in the oxygen-free conditions of the Archean oceans, also in the absence of enzymes, catalyzed by metal. In most organisms, glycolysis occurs in the liquid part of cells, the cytosol. The most common type of glycolysis is the ''Embden–Meyerhof–Parnas (EMP) pathway'', which was discovered by Gustav Embden, Otto Meyerhof, and Jakub Karol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Hydroxy Acids
α-Hydroxy acids, or alpha hydroxy acids (AHAs), are a class of chemical compounds that consist of a carboxylic acid with a hydroxyl group substituent on the adjacent (alpha) carbon. Prominent examples are glycolic acid, lactic acid, mandelic acid and citric acid. Although these compounds are related to the ordinary carboxylic acids and are therefore weak acids, their chemical structure allows for the formation of an internal hydrogen bond between the hydrogen at the hydroxyl group and one of the oxygen atoms of the carboxylic group. The net effect is an increase in acidity. For example, the pKa of lactic acid is 3.86, while that of the unsubstituted propionic acid is 4.87; a full pKa unit difference means that lactic acid is ten times stronger than propionic acid. Industrial applications Feed additives 2-Hydroxy-4-(methylthio)butyric acid is produced commercially as a racemic mixture to substitute for methionine in animal feed. In nature, the same compound is an intermediate in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar Acids
A Sugar acid or acidic sugar is a monosaccharide with a carboxyl group at one end or both ends of its chain. Main classes of sugar acids include: * Aldonic acids, in which the aldehyde group (−CHO) located at the initial end ( position 1) of an aldose is oxidized. * Ulosonic acids, in which the −CH2(OH) group at the initial end of a 2-ketose is oxidized creating an α-ketoacid. * Uronic acids, in which the −CH2(OH) group at the terminal end of an aldose or ketose is oxidized. * Aldaric acids, in which both ends (−CHO and −CH2(OH)) of an aldose are oxidized. Examples Examples of sugar acids include: * Aldonic acids ** Glyceric acid (3C) ** Xylonic acid (5C) ** Gluconic acid (6C) ** Ascorbic acid (6C, unsaturated lactone) * Ulosonic acids ** Neuraminic acid (5-amino-3,5-dideoxy-D- ''glycero''-D- ''galacto''-non-2-ulosonic acid) ** Ketodeoxyoctulosonic acid (KDO or 3-deoxy-D- ''manno''-oct-2-ulosonic acid) * Uronic acids ** Glucuronic acid (6C) ** Galacturonic acid (6C) * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cysteine
Cysteine (symbol Cys or C; ) is a semiessential proteinogenic amino acid with the formula . The thiol side chain in cysteine often participates in enzymatic reactions as a nucleophile. When present as a deprotonated catalytic residue, sometimes the symbol Cyz is used. The deprotonated form can generally be described by the symbol Cym as well. The thiol is susceptible to oxidation to give the disulfide derivative cystine, which serves an important structural role in many proteins. In this case, the symbol Cyx is sometimes used. When used as a food additive, it has the E number E920. Cysteine is encoded by the codons UGU and UGC. The sulfur-containing amino acids cysteine and methionine are more easily oxidized than the other amino acids. Structure Like other amino acids (not as a residue of a protein), cysteine exists as a zwitterion. Cysteine has chirality in the older / notation based on homology to - and -glyceraldehyde. In the newer ''R''/''S'' system of designating chi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycine
Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable), with the chemical formula NH2‐ CH2‐ COOH. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine is integral to the formation of alpha-helices in secondary protein structure due to its compact form. For the same reason, it is the most abundant amino acid in collagen triple-helices. Glycine is also an inhibitory neurotransmitter – interference with its release within the spinal cord (such as during a ''Clostridium tetani'' infection) can cause spastic paralysis due to uninhibited muscle contraction. It is the only achiral proteinogenic amino acid. It can fit into hydrophilic or hydrophobic environments, due to its minimal side chain of only one hydrogen atom. History and etymology Glycine was discovered in 1820 by the French chemist He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine
Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form under biological conditions), and a side chain consisting of a hydroxymethyl group, classifying it as a polar amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC. Occurrence This compound is one of the naturally occurring proteinogenic amino acids. Only the L-stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, ''sericum''. Serine's structure was estab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling life ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Merck Index
''The Merck Index'' is an encyclopedia of chemical substance, chemicals, pharmaceutical drug, drugs and biomolecule, biologicals with over 10,000 monographs, monograph on single substances or groups of related chemical compound, compounds published online by the Royal Society of Chemistry. History The first edition of the Merck's Index was published in 1889 by the German chemical company Merck Group, Emanuel Merck and was primarily used as a sales catalog for Merck's growing list of chemicals it sold. The American subsidiary was established two years later and continued to publish it. During World War I the US government seized Merck's US operations and made it a separate American "Merck" company that continued to publish the Merck Index. In 2012 the Merck Index was licensed to the Royal Society of Chemistry. An online version of The Merck Index, including historic records and new updates not in the print edition, is commonly available through research libraries. It also include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sugar Acid
A Sugar acid or acidic sugar is a monosaccharide with a carboxyl group at one end or both ends of its chain. Main classes of sugar acids include: * Aldonic acids, in which the aldehyde group (−CHO) located at the initial end ( position 1) of an aldose is oxidized. * Ulosonic acids, in which the −CH2(OH) group at the initial end of a 2-ketose is oxidized creating an α-ketoacid. * Uronic acids, in which the −CH2(OH) group at the terminal end of an aldose or ketose is oxidized. * Aldaric acids, in which both ends (−CHO and −CH2(OH)) of an aldose are oxidized. Examples Examples of sugar acids include: * Aldonic acids ** Glyceric acid (3C) ** Xylonic acid (5C) ** Gluconic acid (6C) ** Ascorbic acid (6C, unsaturated lactone) * Ulosonic acids ** Neuraminic acid (5-amino-3,5-dideoxy-D- ''glycero''-D- ''galacto''-non-2-ulosonic acid) ** Ketodeoxyoctulosonic acid (KDO or 3-deoxy-D- ''manno''-oct-2-ulosonic acid) * Uronic acids ** Glucuronic acid (6C) ** Galacturonic acid (6C) * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,3-bisphosphoglyceric Acid
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] |
