title: Properties of bacteriophage T4 mutants defective in gene 30 (deoxyribonucleic acid ligase) and the rII gene.
abstract: In Escherichia coli K-12 strains infected with phage T4 which is defective in gene 30 [deoxyribonucleic acid (DNA) ligase] and in the rII gene (product unknown), near normal levels of DNA and viable phage were produced. Growth of such T4 ligase-rII double mutants was less efficient in E. coli B strains which show the "rapidlysis" phenotype of rII mutations. In pulse-chase experiments coupled with temperature shifts and with inhibition of DNA synthesis, it was observed that DNA synthesized by gene 30-defective phage is more susceptible to breakdown in vivo when the phage is carrying a wild-type rII gene. Breakdown was delayed or inhibited by continued DNA synthesis. Mutations of the rII gene decreased but did not completely abolish the breakdown. T4 ligase-rII double mutants had normal sensitivity to ultraviolet irradiation.
mesh_terms: D003090:Coliphages / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism / Q000528:radiation effects; D003470:Culture Media; D004254:DNA Nucleotidyltransferases / Q000096:biosynthesis*; D004260:DNA Repair; D004261:DNA Replication; D004269:DNA, Bacterial / Q000096:biosynthesis; D004279:DNA, Viral / Q000096:biosynthesis; D004926:Escherichia coli / Q000254:growth & development / Q000378:metabolism; D005796:Genes; D005827:Genetics, Microbial; D008967:Molecular Biology; D009154:Mutation; D011830:Radiation Effects; D013936:Thymidine / Q000378:metabolism; D014316:Tritium; D014466:Ultraviolet Rays; D014779:Virus Replication
chemical_list: D003470:Culture Media; D004269:DNA, Bacterial; D004279:DNA, Viral; D014316:Tritium; D004254:DNA Nucleotidyltransferases; D013936:Thymidine