title: Effects of recB, recF and uvrA mutations on Weigle reactivation of lambda phages in Escherichia coli K12 treated with 8-methoxypsoralen or angelicin and 365-nm light.
abstract: The extent of Weigle reactivation (W-R) of lambda c+ phages treated with bifunctional 8-methoxypsoralen and 365-nm light (8-MOP + UVA) and with monofunctional angelicin and 365-nm light (ANG + UVA) were compared in Escherichia coli strains with different excision repair and recombinational capacities. In uvrA6 host cells, irradiation of the cells with 254-nm radiation only decreased the survival of phages treated with 8-MOP + UVA. The extent of W-R of ANG + UVA-treated phages in uvrA6 cells, however, was much larger than that obtained in other host cells. These results indicate that monoadducts produced by ANG + UVA treatment can be repaired effectively by the repair induced without uvrA gene products, but lesions produced by 8-MOP + UVA treatment cannot be repaired by the repair. The small W-R of ANG + UVA-treated phages in wild-type cells may be due to the high repairability of the lesions by constitutive excision repair in the cells. recB21 reduced only a little of the W-R of 8-MOP + UVA- or ANG + UVA-treated phages obtained in wild-type cells. Although recF143 cells have an almost comparable host-cell repair capacity of 8-MOP + UVA- or ANG + UVA-treated phages to that of the wild-type cells, recF143 mutation reduced not only the extent of W-R of 8-MOP + UVA-treated phages to 17% of that obtained in wild-type cells but also the extent of W-R of ANG + UVA-treated phages to 12% of that obtained in uvrA6 cells.
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000528:radiation effects; D010582:Bacteriophage lambda / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D004260:DNA Repair / Q000528:radiation effects; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D011564:Furocoumarins / Q000633:toxicity*; D007364:Intercalating Agents / Q000633:toxicity*; D007700:Kinetics; D008730:Methoxsalen / Q000633:toxicity*; D009154:Mutation; D014466:Ultraviolet Rays
chemical_list: D001426:Bacterial Proteins; D011564:Furocoumarins; D007364:Intercalating Agents; C011659:angelicin; D008730:Methoxsalen