title: Effect of a gene-specific suppressor mutation (das) on DNA synthesis of gene 46-47 mutants of bacteriophage T4D.
abstract: Mutants in genes 46 and 47 of bacteriophage T4 exhibit early cessation of DNA synthesis, inability to form a normal rapidly sedimenting DNA intermediate (200S), reduced genetic recombination, and reduced viable phage production. A gene-specific suppressor mutation called das partially restores many of the pleiotropic effects of gene 46-47 mutants (13). Our results indicate that this partial suppression by das is associated with (i) the synthesis of a small fraction of DNA containing long single chains not detectable in 46-47 infection and (ii) a decrease in an "early" function which participates in the degradation of DNA synthesized in the absence of 46-47 functions. However, das does not restore the formation of a normal rapidly sedimenting (200S) DNA intermediate.
mesh_terms: D002499:Centrifugation, Density Gradient; D002701:Chloramphenicol / Q000494:pharmacology; D003090:Coliphages / Q000032:analysis / Q000378:metabolism*; D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis / Q000096:biosynthesis*; D004926:Escherichia coli; D009154:Mutation; D009691:Nucleic Acid Denaturation; D010761:Phosphorus Radioisotopes; D013395:Sucrose; D013489:Suppression, Genetic; D013936:Thymidine / Q000378:metabolism; D014316:Tritium
chemical_list: D004277:DNA, Single-Stranded; D004279:DNA, Viral; D010761:Phosphorus Radioisotopes; D014316:Tritium; D013395:Sucrose; D002701:Chloramphenicol; D013936:Thymidine