Ecto-Nucleoside Triphosphate Diphosphohydrolase Activities in Trypanosomatids:Possible Roles in Infection, Virulence and Purine Recycling

摘要

Ecto-nucleoside triphosphate diphosphohydrolases (ecto-NTPDases), also known as ecto-ATPases and/or ectoapyrases,are integral membrane glycoproteins or soluble enzymes that are dependent on divalent cations. These ectoenzymesare important ecto-nucleotidases that are characterized by the ability to hydrolyze nucleoside triphosphates andnucleoside diphosphates to the monophosphate form. The hydrolysis of nucleoside monophosphates to nucleosides suchas adenosine may then be catalyzed by the action of ecto-5′nucleotidases. The present study reviews the sequential hydrolysisof ATP → ADP → AMP → adenosine catalyzed by these ecto-enzymes from different trypanosomatids. Thesereactions participate in the salvage of purines in these parasites and simultaneously interfere with the establishment of infectionand changes in the host immune response.