Ecto-nucleotidases of ectonucleoside triphosphate diphosphohydrolase family: structure, localization and functional significance

Ecto-nucleotidases are enzymes of hydrolase class. They split extracellular nucleoside tri- and diphosphate. In this review a short history of these enzymes investigation, classification, structure, and functional significance of ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDase) has been presented. These enzymes are glycoproteins anchored in membranes. They do not form phosphorylated enzyme's form during catalytic circle, and (by analogy with membrane-bound ATPases) form homooligomeric ensembles. Activity of these enzymes depends on bivalent ions, in particular Ca2+ and Mg2+. E-NTPDases function in the composition of ecto-nucleotidase cascade that contains other nucleotide-hydrolyzing enzymes. They regulate P2-receptors by hydrolyzing its ligand specifically ATP. Both modern information and results of our investigation about influence of different endo- and exogenous factors on activity of these enzymes has been presented.