| GTP-binding protein | <molecular biology, protein> There are two main classes of G-proteins, the heterotrimeric G proteins that associate with receptors of the seven transmembrane domain superfamily and are involved in signal transduction and the small cytoplasmic G-proteins. Regulatory proteins found in all cells. They are versatile molecular switches, involved in the control of a wide range of biological processes - protein synthesis, signal transduction pathways, growth and differentiation. They all act through a common molecular mechanism based on their ability to bind the guanine nucleotides GTP and GDP selectively and with high affinity. Stimulatory G-proteins are permanently activated by cholera toxin, inhibitory ones by pertussis toxin. Transducin was one of the first of the heterotrimeric G-proteins to be identified. The small G-proteins are a diverse group of monomeric GTPases that include ras, rab, rac and rho and that play an important part in regulating many intracellular processes including cytoskeletal organisation and secretion. Their GTPase activity is regulated by activators (GAPs) and inhibitors (GIPs) that determine the duration of the active state. (12 Jul 2000) |
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| RLK5-associated protein phosphatase | <enzyme> Associated with serine-threonine receptor-like kinase, rlk5; from arabidopsis thaliana; composed of 3 domains, an amino-terminal signal anchor, a kinase interaction domain and a type 2c protein phosphatase catalytic domain; mw 65 kD; genbank u09505 Registry number: EC 3.1.3.- Synonym: kapp, kinase-associated protein phosphatase (26 Jun 1999) |
| guanosine triphosphate binding protein | <protein> A type of protein embedded in the cytoplasmic membrane of the cell which transmits signals from outside the cell (such as from hormones binding to receptors on the outside of the cell) to the inside of the cell, where it causes some sort of biochemical reaction within the cell to the signal (such as the altering of metabolic pathways or gene expression). The process by which the protein does this is unclear but involves exchanging a molecule of GDP for a molecule of GTP. (09 Oct 1997) |
| methyl accepting chemotaxis protein | Methyl accepting chemotaxis proteins. Proteins of the inner cytoplasmic face of the bacterial plasma membane with which the receptors of the outer face interact. Four different MCPs are known in E. Coli, each with a separate set of receptors. Can be methylated at various sites, methylation is part of the adaptation to the signal. Although important intermediate signal integration sites, they are not directly connected to the motor. (18 Nov 1997) |
| PfKIN protein kinase | <enzyme> Snf1 type protein kinase from plasmodium flaciparum; genbank z22868 Registry number: EC 2.7.10.- (26 Jun 1999) |
| MHC class II protein | <protein> The antigen-presenting molecule found primarily on macrophages and B lymphocytes. (09 Oct 1997) |
| MHC class I protein | <protein> The antigen-presenting molecule found on all nucleated vertebrate cells. (09 Oct 1997) |
| phenylthiocarbamoyl protein | Formed by the reaction of phenylisothiocyanate with a terminal alpha-amino group of a peptide or protein See: phenylisothiocyanate, phenylthiohydantoin. Synonym: PhNCS protein, PTC protein. (05 Mar 2000) |
| PhNCS protein | Formed by the reaction of phenylisothiocyanate with a terminal alpha-amino group of a peptide or protein See: phenylisothiocyanate, phenylthiohydantoin. Synonym: PhNCS protein, PTC protein. (05 Mar 2000) |
| microtubule-associated protein 1B kinase | <enzyme> Serine-threonine-specific protein kinase which acts on microtubule-associated protein 1b (map1b); activated by various mitogens; does not act on map2 Registry number: EC 2.7.10.- Synonym: map1b kinase (26 Jun 1999) |
| microtubule-associated protein-2 phosphatase | <enzyme> does not fit into any of the classes of protein phosphatases (types 1,2a,2b and 2c) involved in cellular regulation Registry number: EC 3.1.3.- Synonym: map-2 phosphatase (26 Jun 1999) |
| cis-acting protein | A protein that acts on the molecule of DNA from which it was expressed. (05 Mar 2000) |
| phosphoenolpyruvate-protein phosphotransferase | <enzyme> Enzyme I of the system Registry number: EC 2.7.3.9 Synonym: enzyme I, phosphoenolpyruvate sugar phosphotransferase system, enzyme I peppts, ptsi gene product, ptsj gene product, ptsp gene product, enzyme i(ntr) (26 Jun 1999) |
| mild silver protein | A complex prepared by the reaction of silver oxide with either gelatin or serum albumin. Black shiny crystals liberate silver and it was formerly widely used as a topical anti-infective on mucous membranes. Contains from 19 to 25% silver, only a small fraction of which is ionizable. Can produce black or brown pigmentation due to deposition of reduced silver in the tissues. Synonym: argyrol, silvol. (05 Mar 2000) |
| phospholipid transfer protein | <protein> Cytoplasmic proteins that bind phospholipids and facilitate their transfer between cellular membranes. May also cause net transfer from the site of synthesis. (18 Nov 1997) |