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B-6. Six conditional lethal te mutants of phage T4 ( af) are isolated and crossed in all pairwise combinations to three T4 deletion mutants (1-3) with the results shown below. point mutant b с d e a f OOO 0 2 3 0 + 0 0 0 0 0 0 0 0 + + + + + + = wild type recombinants 0 = no wild type recombinants When the te mutants were tested in all possible pairs for complementation, the results below were obtained. f e d с b b a a + + 0 + + 0 b + + + + 0 с + 0 0 + O d + + + 0 e + 0 f 0 + + complementation 0 = no complementation Assuming there is no intragenic complementation between any of these te mutants, combine the deletion mapping and complementation results to determine the most likely relative order of the six mutations. Draw boxes around mutations that are in the same gene (one box for each gene) and use lines below your map to show the position and extent of deletions 1, 2 and 3.

8-7. Eight different ta mutants (#1-8) of T4 are isolated and studied by complementation tests and by deletion mapping. All of the te mutants can make plaques at 30° but not at 40°. The results of all pairwise complementation tests are shown below. 2. 3 8 0 FI + 7 + 0 ++ 4 0 + + + 6 + + 0 + 5 + + + 0 1 + 0 + + + + + 0 8 7 6 5 4 3 2 1 0 + Noon + 0 + 0 + + 0 + = progeny made 0 = no progeny made (a) Describe in words and/or diagrams exactly how such a test should be done. Be sure to indicate the temperature at which each step is carried out. (6) Classify these eight mutants into genes. The eight te mutants are crossed to three T4 deletion mutants with the results shown below. 2 3 4 5 6 6 7 8 0 0 Good + + 0 AO B + С + + + + + 0 0 + OO NOOC 0 + 0 + + 0 0 = no wild type recombinants + = wild type recombinants formed (c) Taking both these and the complementation data into account, indicate the order of mutations 1-8 on the T4 chromosome. Draw circles around mutations in the same gene. Also draw three lines beneath the map to indicate the position and extent of deletions A, B, C.