Phosphorylase

Phosphorylase

Phosphorylase is a family of allosteric enzymes that catalyze the production of glucose-1-phosphate from a polyglucose such as glycogen, starch or maltodextrin.

Function

More generally, phosphorylases are enzymes that catalyze the addition of a phosphate group from an inorganic phosphate (phosphate+hydrogen) to an acceptor. Do not confuse this enzyme with a phosphatase or a kinase. A phosphatase removes a phosphate group from a donor, while a kinase transfers a phosphate group from a donor (usually ATP) to an acceptor.

Types

The phosphorylases are named by prepending the name of the substrate, e.g. glycogen phosphorylase, starch phosphorylase, maltodextrin phosphorylase.

All known phosphorylases share catalytic and structural properties [http://www.expasy.org/cgi-bin/nicedoc.pl?PDOC00095] .

Activation

Phosphorylase a is the active form of glycogen phosphorylase that is derived from the phosphorylation of the inactive form, phosphorylase b.

Pathology

Some disorders are related to phosphorylases:

* Glycogen storage disease type V - muscle glycogen
* Glycogen storage disease type VI - liver glycogen

External links

*


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Look at other dictionaries:

  • phosphorylase — [ fɔsfɔrilaz ] n. f. • 1949; de phosphoryle et ase ♦ Biochim. Enzyme responsable de la dégradation du glycogène dans le muscle et dans le foie. phosphorylase [fɔsfɔʀilaz] n. f. ÉTYM. 1949, cit.; de phosphoryle, et suff. ase. ❖ …   Encyclopédie Universelle

  • phosphorylase — [fäs′fə ri lās΄] n. [ PHOSPHOR(O) + YL + ASE] any of a group of enzymes, widely distributed in plant and animal tissues, that help inorganic phosphates break down glycogen and other complex sugars …   English World dictionary

  • Phosphorylase — Dieser Artikel oder Abschnitt bedarf einer Überarbeitung. Hilf mit, ihn zu verbessern, und entferne anschließend diese Markierung. Als Phosphorylasen bezeichnet man eine Familie allosterischer Enzyme, welche die Produktion von Glukose 1 Phosphat… …   Deutsch Wikipedia

  • phosphorylase — A phosphorylated enzyme cleaving poly(1,4 α d glucosyl)n with orthophosphate to form poly(1,4 α d glucosyl)n−1 and α d glucose 1 phosphate. SYN: α glucan p., glycogen p., P enzyme, p. a, polyphosphorylase. p. a SYN: p.. p. b dephosphorylated p. a …   Medical dictionary

  • Phosphorylase — Phos|pho|ry|la|se [↑ Phosphoryl u. ↑ ase], die; , n: Bez. für ein in Leber u. Muskeln vorkommendes, als Transferase wirkendes Enzym, das Glykogen unter Bildung von Glucose 1 phosphat abbaut (↑ Phosphorolyse). Die aktive Form der P. (Phosphorylase …   Universal-Lexikon

  • phosphorylase — (= glycogen phosphorylase) Enzyme that catalyses the sequential removal of glycosyl residues from glycogen to yield one glucose 1 phosphate per reaction. Its activity is controlled by phosphorylation (by phosphorylase kinase) …   Dictionary of molecular biology

  • phosphorylase — n. any enzyme that catalyses the combination of an organic molecule (usually glucose) with a phosphate group (phosphorylation). Phosphorylase is found in the liver and kidney, where it is involved in the breakdown of glycogen to glucose 1… …   The new mediacal dictionary

  • phosphorylase — noun Date: 1939 any of the enzymes that catalyze phosphorolysis with the formation of organic phosphates …   New Collegiate Dictionary

  • Phosphorylase — Les phosphorylases sont les enzymes responsables de la phosphorolyse. Ils ajoutent un ion phosphate PO43 (ou orthophosphate) à partir d un ion hydrogénophosphate HPO42 (parfois appelé phosphate inorganique[1] ou encore phosphate d hydrogène) sur… …   Wikipédia en Français

  • phosphorylase — /fos feuhr euh lays , layz , fos fawr euh , for /, n. Biochem. any enzyme, occurring widely in animal and plant tissue, that in the presence of an inorganic phosphate catalyzes the conversion of glycogen into sugar phosphate. [1935 40; PHOSPHOR + …   Universalium

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