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Nucleotide Kinase
A nucleotide kinase is any kinase taking a nucleotide reactant. It may mean: * Nucleoside-phosphate kinase, EC 2.7.4.4 * Nucleoside-diphosphate kinase, EC 2.7.4.6 * (deoxy)nucleoside-phosphate kinase, EC 2.7.4.10 * Nucleoside-triphosphate—adenylate kinase, EC 2.7.4.13 * Cytidylate kinase, EC 2.7.4.14 {{set index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinase
In biochemistry, a kinase () is an enzyme that catalyzes the transfer of phosphate groups from high-energy, phosphate-donating molecules to specific substrates. This process is known as phosphorylation, where the high-energy ATP molecule donates a phosphate group to the substrate molecule. This transesterification produces a phosphorylated substrate and ADP. Conversely, it is referred to as dephosphorylation when the phosphorylated substrate donates a phosphate group and ADP gains a phosphate group (producing a dephosphorylated substrate and the high energy molecule of ATP). These two processes, phosphorylation and dephosphorylation, occur four times during glycolysis. Kinases are part of the larger family of phosphotransferases. Kinases should not be confused with phosphorylases, which catalyze the addition of inorganic phosphate groups to an acceptor, nor with phosphatases, which remove phosphate groups (dephosphorylation). The phosphorylation state of a molecule, whet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleotide
Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver. Nucleotides are composed of three subunit molecules: a nucleobase, a five-carbon sugar (ribose or deoxyribose), and a phosphate group consisting of one to three phosphates. The four nucleobases in DNA are guanine, adenine, cytosine and thymine; in RNA, uracil is used in place of thymine. Nucleotides also play a central role in metabolism at a fundamental, cellular level. They provide chemical energy—in the form of the nucleoside triphosphates, adenosine triphosphate (ATP), guanosine triphosphate (GTP), cytidine triphosphate (CTP) and uridine triphosphate (UTP)—throughout the cell for the many cellular func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleoside-phosphate Kinase
In enzymology, a nucleoside-phosphate kinase () is an enzyme that catalyzes the chemical reaction :ATP + nucleoside phosphate \rightleftharpoons ADP + nucleoside diphosphate Thus, the two substrates of this enzyme are ATP and nucleoside monophosphate, whereas its two products are ADP and nucleoside diphosphate. This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with a phosphate group as acceptor. The systematic name of this enzyme class is ATP:nucleoside-phosphate phosphotransferase. This enzyme is also called NMP-kinase, or nucleoside-monophosphate kinase. Structure A number of crystal structures have been solved for this class of enzymes, revealing that they share a common ATP binding domain. This section of the enzyme is commonly referred to as the P-loop, in reference to its interaction with the phosphoryl groups on ATP. This binding domain also consists of a β sheet flanked by α ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleoside-diphosphate Kinase
Nucleoside-diphosphate kinases (NDPKs, also NDP kinase, (poly)nucleotide kinases and nucleoside diphosphokinases) are enzymes that catalyze the exchange of terminal phosphate between different nucleoside diphosphates (NDP) and triphosphates (NTP) in a reversible manner to produce nucleotide triphosphates. Many NDP serve as acceptor while NTP are donors of phosphate group. The general reaction via ping-pong mechanism is as follows: XDP + YTP ←→ XTP + YDP (X and Y each represent different nitrogenous base). NDPK activities maintain an equilibrium between the concentrations of different nucleoside triphosphates such as, for example, when guanosine triphosphate (GTP) produced in the citric acid (Krebs) cycle is converted to adenosine triphosphate (ATP). Other activities include cell proliferation, differentiation and development, signal transduction, G protein-coupled receptor, endocytosis, and gene expression. Structure NDPK are homo hexameric proteins made up of monomers appro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
(deoxy)nucleoside-phosphate Kinase
In enzymology, a (deoxy)nucleoside-phosphate kinase () is an enzyme that catalyzes the chemical reaction :ATP + deoxynucleoside phosphate \rightleftharpoons ADP + deoxynucleoside diphosphate Thus, the two substrates of this enzyme are ATP and deoxynucleoside phosphate, whereas its two products are ADP and deoxynucleoside diphosphate. This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferase Phosphotransferases are a category of enzymes ( EC number 2.7) that catalyze phosphorylation reactions. The general form of the reactions they catalyze is: :A-P + B \rightleftharpoons B-P + A Where ''P'' is a phosphate group and A and B are the do ...s) with a phosphate group as acceptor. The systematic name of this enzyme class is ATP:deoxynucleoside-phosphate phosphotransferase. Other names in common use include deoxynucleoside monophosphate kinase, deoxyribonucleoside monophosphokinase, and deoxynucleoside-5' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleoside-triphosphate—adenylate Kinase
In enzymology, a nucleoside-triphosphate-adenylate kinase () is an enzyme that catalyzes the chemical reaction :nucleoside triphosphate + AMP \rightleftharpoons nucleoside diphosphate + ADP Thus, the two substrates of this enzyme are nucleoside triphosphate and AMP, whereas its two products are nucleoside diphosphate and ADP. This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferase Phosphotransferases are a category of enzymes ( EC number 2.7) that catalyze phosphorylation reactions. The general form of the reactions they catalyze is: :A-P + B \rightleftharpoons B-P + A Where ''P'' is a phosphate group and A and B are the do ...s) with a phosphate group as acceptor. The systematic name of this enzyme class is nucleoside-triphosphate:AMP phosphotransferase. Other names in common use include guanosine triphosphate-adenylate kinase, nucleoside triphosphate-adenosine monophosphate transphosphorylas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
