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Working with genes, mutations and recombination

Six mutants in the rII region of phage T4 were independently isolated. Recombination to produce wild-type progeny occurred between all of these mutants. Pairwise multiple infections of E.coli strain K12 were made with the results shown below. (The number of phage particles used in each multiple infection was approximately the same, and was constant among experiments).

(a) Fill in a complementation table. Use "+" for complementation and "0" for no complementation.
(b) How many genes are affected among all these mutant strains?
(c) Which mutants have mutations in the same gene(s)?

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In the simplest terms, phages infect bacteria. These infections are called plaques on a plate of growing bacteria (E. coli K12 in this case). While the number of plaques varies, we can say here than any non-zero value represents recombination, since they're all in the same sort of range. If, however there was a plate of E. coli that only had a few plaques, we might suspect that there had ...

Solution Summary

Six mutation regions of phages are determined. A pairwise multiple infections of E. coli strains are examined.