Metabolism of cytosine arabinoside in Tetrahymena pyriformis.
The metabolism of cytosine arabinoside (araC) in Tetrahymena pyriformis amicronucleate strain W was studied. araC inhibited cell multiplication and protein synthesis at concentrations higher than 0.1 and 0.25 M respectively. araC had no effect on protein synthesis. araC was converted to araCMP, araCDP and araCTP by homogenized cell preparations. A deaminase activity converted araC to uracil arabinoside. The deaminase activity totally inhibited by tetrahydrouridine (THU) at a concn of 4 X 10(-6) M. The Ki for THU was 8 X 10(-8) M.
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D003561:Cytarabine / Q000378:metabolism* / Q000494:pharmacology; D004261:DNA Replication / Q000187:drug effects; D007700:Kinetics; D009700:Nucleoside Deaminases / Q000378:metabolism; D013767:Tetrahydrouridine / Q000494:pharmacology; D013769:Tetrahymena pyriformis / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
D003561:Cytarabine; D013767:Tetrahydrouridine; D009700:Nucleoside Deaminases; C019717:arabinosylcytosine deaminase