title: The partial purification and characterization of adenosine kinase from Entamoeba histolytica.
abstract: Axenically grown Entamoeba histolytica was found to contain adenosine kinase. This organism lacks de novo purine biosynthetic pathways. Adenosine kinase provides the amoeba with a method for salvaging adenosine from ingested nucleosides or from degraded nucleotides. Adenosine kinase was purified 64-fold, by chromatography on Sephacryl S-200, DEAE-cellulose, and (C-8)-adenosine-agarose. The latter separated it from amebal adenylate kinase. Adenosine kinase has a molecular weight of 38,000 and requires glycerol for stability. It utilizes adenosine triphosphate to phosphorylate adenosine, and 7-deazaadenosine (tubercidin), but adenine 9-beta-D-arabinofuranoside (ara-A) is not detectably phosphorylated. It requires Mg++ as a cofactor.
mesh_terms: D000241:Adenosine / Q000378:metabolism; D000248:Adenosine Kinase / Q000302:isolation & purification* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002846:Chromatography, Affinity; D004748:Entamoeba histolytica / Q000201:enzymology*; D005990:Glycerol / Q000494:pharmacology; D007700:Kinetics; D010770:Phosphotransferases / Q000302:isolation & purification*; D013379:Substrate Specificity; D014372:Tubercidin / Q000378:metabolism; D014740:Vidarabine / Q000378:metabolism
chemical_list: D000255:Adenosine Triphosphate; D010770:Phosphotransferases; D000248:Adenosine Kinase; D014740:Vidarabine; D000241:Adenosine; D014372:Tubercidin; D005990:Glycerol