Time-of-entry experiments indicate that a gene for resistance to kanamycin, kan-r, is closely linked to a gene for resistance to bacteriophage T5, T5-r. A geneticist has strains of two genotypes available, kan-r T5-s (resistant to kanamycin, sensitive to phage T5) and kan-s T5-r (sensitive to kanamycin, resistant to phage T5). In an experiment using phage P1 to learn whether the genes are close enough for cotransduction, how would the experiment be done?

Part A: Specifically, which strain would you use to generate the transducing phage and which stain would you infect with this phage?

Part B: What methods would you use to determine if the genes had been co-transduced in the recipient cell?