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1-Pyrroline-5-carboxylate Dehydrogenase
In enzymology, a 1-pyrroline-5-carboxylate dehydrogenase () is an enzyme that catalyzes the chemical reaction : (S)-1-pyrroline-5-carboxylate + NAD+ + 2 H2O \rightleftharpoons L-glutamate + NADH + H+ The three substrates of this enzyme are (''S'')-1-pyrroline-5-carboxylate, NAD+, and H2O, whereas its three products are glutamate, NADH, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-NH group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is (''S'')-1-pyrroline-5-carboxylate:NAD+ oxidoreductase. Other names in common use include delta-1-pyrroline-5-carboxylate dehydrogenase, 1-pyrroline dehydrogenase, pyrroline-5-carboxylate dehydrogenase, pyrroline-5-carboxylic acid dehydrogenase, L-pyrroline-5-carboxylate-NAD+ oxidoreductase, and 1-pyrroline-5-carboxylate:NAD+ oxidoreductase. This enzyme participates in glutamate metabolism and arginine and proline metabolism. Structural studies As o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzymology
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Ion
A hydrogen ion is created when a hydrogen atom loses or gains an electron. A positively charged hydrogen ion (or proton) can readily combine with other particles and therefore is only seen isolated when it is in a gaseous state or a nearly particle-free space. Due to its extremely high charge density of approximately 2×1010 times that of a sodium ion, the bare hydrogen ion cannot exist freely in solution as it readily hydrates, i.e., bonds quickly. The hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions. Cation (positively charged) A hydrogen atom is made up of a nucleus with charge +1, and a single electron. Therefore, the only positively charged ion possible has charge +1. It is noted H+. Depending on the isotope in question, the hydrogen cation has different names: * Hydron: general name referri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ALDH4A1
Delta-1-pyrroline-5-carboxylate dehydrogenase, mitochondrial is an enzyme that in humans is encoded by the ''ALDH4A1'' gene. This protein belongs to the aldehyde dehydrogenase family of proteins. This enzyme is a mitochondrial matrix NAD-dependent dehydrogenase that catalyzes the second step of the proline degradation pathway, converting pyrroline-5-carboxylate to glutamate. Deficiency of this enzyme is associated with type II hyperprolinemia, an autosomal recessive disorder characterized by accumulation of delta-1-pyrroline-5-carboxylate (P5C) and proline. Two transcript variants encoding the same protein have been identified for this gene. References External links * PDBe-KBprovides an overview of all the structure information available in the PDB for Human Delta-1-pyrroline-5-carboxylate dehydrogenase, mitochondrial (ALDH4A1) PDBe-KBprovides an overview of all the structure information available in the PDB for Mouse Delta-1-pyrroline-5-carboxylate dehydrogenase, mitochondria ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Data Bank
The Protein Data Bank (PDB) is a database for the three-dimensional structural data of large biological molecules, such as proteins and nucleic acids. The data, typically obtained by X-ray crystallography, NMR spectroscopy, or, increasingly, cryo-electron microscopy, and submitted by biologists and biochemists from around the world, are freely accessible on the Internet via the websites of its member organisations (PDBe, PDBj, RCSB, and BMRB). The PDB is overseen by an organization called the Worldwide Protein Data Bank, wwPDB. The PDB is a key in areas of structural biology, such as structural genomics. Most major scientific journals and some funding agencies now require scientists to submit their structure data to the PDB. Many other databases use protein structures deposited in the PDB. For example, SCOP and CATH classify protein structures, while PDBsum provides a graphic overview of PDB entries using information from other sources, such as Gene ontology. History Two force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary Structure
Protein tertiary structure is the three dimensional shape of a protein. The tertiary structure will have a single polypeptide chain "backbone" with one or more protein secondary structures, the protein domains. Amino acid side chains may interact and bond in a number of ways. The interactions and bonds of side chains within a particular protein determine its tertiary structure. The protein tertiary structure is defined by its atomic coordinates. These coordinates may refer either to a protein domain or to the entire tertiary structure.Branden C. and Tooze J. "Introduction to Protein Structure" Garland Publishing, New York. 1990 and 1991. A number of tertiary structures may fold into a quaternary structure.Kyte, J. "Structure in Protein Chemistry." Garland Publishing, New York. 1995. History The science of the tertiary structure of proteins has progressed from one of hypothesis to one of detailed definition. Although Emil Fischer had suggested proteins were made of polypept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arginine And Proline Metabolism Arginine and proline metabolism is one of the central pathways for the biosynthesis of the amino acids arginine and proline from glutamate. The pathways linking arginine, glutamate, and proline are bidirectional. Thus, the net utilization or production of these amino acids is highly dependent on cell type and developmental stage. Altered proline metabolism has been linked to metastasis formation in breast cancer. Reactions Proline is biosynthetically derived from the amino acid L-glutamate. Glutamate-5-semialdehyde is first formed by glutamate 5-kinase (ATP-dependent) an |
