title: Thymineless mutagenesis in bacteriophage T4.
abstract: Thymine deprivation can be achieved in bacteriophage T4 either by the use of the thymidylate synthetase inhibitor FUdR, or by an appropriate combination of genetic blocks; both methods produce marked mutagenesis. Extensive tests of the specificity of thymineless mutagenesis reveal that only A:T base pairs are affected, and that transitions and possibly transversions are produced. This system therefore constitutes the first example of an A:T-specific mutagen. Thymineless mutagenesis in bacteriophage T4 exhibits a marked dependence upon the functional state of the DNA polymerase gene, but is largely independent of the px-y misrepair system.
mesh_terms: D000227:Adenine Nucleotides; D000483:Alleles; D001973:Bromodeoxyuridine / Q000494:pharmacology; D003090:Coliphages / Q000378:metabolism; D003597:Cytosine Nucleotides; D004254:DNA Nucleotidyltransferases; D004260:DNA Repair; D004269:DNA, Bacterial / Q000096:biosynthesis; D004926:Escherichia coli / Q000378:metabolism; D005467:Floxuridine / Q000494:pharmacology; D006150:Guanine Nucleotides; D009154:Mutation / Q000187:drug effects; D011995:Recombination, Genetic; D013696:Temperature; D013936:Thymidine / Q000494:pharmacology; D013940:Thymidylate Synthase / Q000037:antagonists & inhibitors; D013941:Thymine; D013942:Thymine Nucleotides; D014529:Uridine / Q000494:pharmacology
chemical_list: D000227:Adenine Nucleotides; D003597:Cytosine Nucleotides; D004269:DNA, Bacterial; D006150:Guanine Nucleotides; D013942:Thymine Nucleotides; D005467:Floxuridine; D013940:Thymidylate Synthase; D004254:DNA Nucleotidyltransferases; D001973:Bromodeoxyuridine; D013941:Thymine; D013936:Thymidine; D014529:Uridine