Apyrase

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Apyrase
PDB 1s18 EBI.jpg
structure and protein design of human apyrase
Identifiers
Symbol Apyrase
Pfam PF06079
InterPro IPR009283
SCOP 1s1d
SUPERFAMILY 1s1d

Apyrase (EC 3.6.1.5, ATP-diphosphatase, adenosine diphosphatase, ADPase, ATP diphosphohydrolase) is a calcium-activated plasma membrane-bound enzyme (magnesium can also activate it) (EC 3.6.1.5) that catalyses the hydrolysis of ATP to yield AMP and inorganic phosphate. Two isoenzymes are found in commercial preparations from S. tuberosum. One with a higher ratio of substrate selectivity for ATP:ADP (approx 10) and another with no selectivity (ratio 1).

It can also act on ADP and other nucleoside triphosphates and diphosphates with the general reaction being NTP -> NDP + Pi -> NMP + 2Pi.

The salivary apyrases of blood-feeding arthropods are nucleotide hydrolysing enzymes are implicated in the inhibition of host platelet aggregation through the hydrolysis of extracellular adenosine diphosphate.[1]


References[edit]

  1. ^ Smith TM, Hicks-Berger CA, Kim S, Kirley TL (October 2002). "Cloning, expression, and characterization of a soluble calcium-activated nucleotidase, a human enzyme belonging to a new family of extracellular nucleotidases". Arch. Biochem. Biophys. 406 (1): 105–15. doi:10.1016/S0003-9861(02)00420-4. PMID 12234496. 

External links[edit]

This article incorporates text from the public domain Pfam and InterPro IPR009283