title: Effect of inhibitors of ribonucleic acid and protein synthesis on the cyclic adenosine monophosphate stimulation of plasmid ColE1 replication.
abstract: Addition of cyclic adenosine 3'-5'-monophosphate (c-AMP) to growing Escherichia coli cells, colicinogenic for the plasmid ColE1, results in a fourfold stimulation in the rate of synthesis of the plasmid deoxyribonucleic acid (DNA). The stimulation is transient (30 min) and is succeeded by a brief period (30 min) of cessation of plasmid DNA replication. The stimulation of ColE1 DNA replication also occurs in chloramphenicol-treated cells. Rifampin inhibits ColE1 DNA replication in the presence or absence of c-AMP. Employing thymine starvation conditions to stop ColE1 DNA synthesis, it was found that c-AMP, added during the period of thymine starvation, effected a stimulation in the amount of subsequent replication which took place when replicating conditions were restored. The stimulatory effect of c-AMP under these conditions was not prevented by chloramphenicol but was completely eliminated when rifampin was present. Under these conditions, when rifampin was added after the effect of c-AMP was allowed to occur, subsequent replication of the plasmid could take place, but only one round of replication occurred. A model to account for the c-AMP effects is presented.
mesh_terms: D002250:Carbon Radioisotopes; D002499:Centrifugation, Density Gradient; D002701:Chloramphenicol / Q000494:pharmacology*; D003087:Colicins / Q000096:biosynthesis; D000242:Cyclic AMP / Q000494:pharmacology*; D004261:DNA Replication / Q000187:drug effects*; D004269:DNA, Bacterial / Q000032:analysis / Q000096:biosynthesis*; D004926:Escherichia coli / Q000378:metabolism*; D005111:Extrachromosomal Inheritance; D012293:Rifampin / Q000494:pharmacology*; D013268:Stimulation, Chemical; D013936:Thymidine / Q000378:metabolism; D013941:Thymine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium
chemical_list: D002250:Carbon Radioisotopes; D003087:Colicins; D004269:DNA, Bacterial; D014316:Tritium; D002701:Chloramphenicol; D000242:Cyclic AMP; D013941:Thymine; D013936:Thymidine; D012293:Rifampin