An RNA-dependent nucleoside triphosphate hydrolase from Krebs-II ascites tumor cells. Detection and preliminary characterization.
A novel enzymatic activity, RNA-dependent, NTPase, was isolated from Krebs-II ascites tumor cells. This activity is associated with ribosomes and can be detached from them by washing in KCl solutions of a higher than 0.3 M concentration. The enzyme hydrolyzes all the four nucleoside triphosphates to the corresponding nucleoside diphosphates and orthophosphate. The rate of NTP hydrolysis increases about 10-fold in the presence of natural RNAs and synthetic polyribonucleotides [except poly(G)]. Natural DNAs, both double and single-stranded, are poor cofactors, although pol(dA) and poly(dT) stimulate, to a certain extent, the rate of ATP hydrolysis. Possible involvement of RNA-dependent NTPase in protein biosynthesis is discussed.
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D002287:Carcinoma, Krebs 2 / Q000201:enzymology*; D055598:Chemical Phenomena; D002621:Chemistry; D002712:Chlorides / Q000494:pharmacology; D006868:Hydrolysis; D051379:Mice; D009363:Neoplasm Proteins / Q000302:isolation & purification*; D043583:Nucleoside-Triphosphatase; D010744:Phosphoric Monoester Hydrolases / Q000302:isolation & purification*; D011061:Poly A / Q000494:pharmacology; D012334:RNA, Neoplasm / Q000302:isolation & purification*; D012269:Ribosomal Proteins / Q000302:isolation & purification; D013379:Substrate Specificity
D002712:Chlorides; D009363:Neoplasm Proteins; D012334:RNA, Neoplasm; D012269:Ribosomal Proteins; D011061:Poly A; D010744:Phosphoric Monoester Hydrolases; D000251:Adenosine Triphosphatases; D043583:Nucleoside-Triphosphatase