title: DIFFERENTIAL MUTATION PRODUCTION BY THE DECAY OF INCORPORATED TRITIUM COMPOUNDS IN E. COLI.
abstract: We have studied the differential mutation production by the decay of incorporated tritium compounds in E. coli (WWU) using DNA-seeking precursors (H(3)-thymidine), RNA-seeking precursors (H(3)-uracil, H(3)-uridine), and protein-seeking precursors (H(3)-histidine, H(3)-proline). In particular we have determined the reversion frequency of an arginine locus. The reversion frequency is measured in units of revertants/surviving bacteria/H(3) decay, and has an average value of 1.84 x 10(-8) for H(3)-uridine and H(3)-uracil, 0.67 x 10(-8) for H(3)-thymidine, and 0.28 x 10(-8) for H(3)-proline and H(3)-histidine. Thus, the revertants are produced most effectively by H(3) decays when the label is introduced in the form of an RNA precursor. The macromolecular distribution of the label shows that 5 to 8 per cent of the H(3)-uridine or H(3)-uracil is incorporated into DNA.
mesh_terms: D001120:Arginine; D004247:DNA; D004269:DNA, Bacterial; D004926:Escherichia coli; D006639:Histidine; D007930:Leucine; D009154:Mutation; D009705:Nucleosides; D011392:Proline; D012313:RNA; D012329:RNA, Bacterial; D013936:Thymidine; D014316:Tritium; D014498:Uracil; D014529:Uridine
chemical_list: D004269:DNA, Bacterial; D009705:Nucleosides; D012329:RNA, Bacterial; D014316:Tritium; D006639:Histidine; D014498:Uracil; D012313:RNA; D004247:DNA; D001120:Arginine; D011392:Proline; D007930:Leucine; D013936:Thymidine; D014529:Uridine
keywords: DNA, BACTERIAL; ESCHERICHIA COLI; HISTIDINE; LEUCINE; MUTATION; NUCLEOSIDES; PROLINE; RNA, BACTERIAL; THYMIDINE; TRITIUM; URACIL