Question

Required information Shown below are the maps of a series of rll-deletion strains (1–5). The deleted region is indicated as (.....) and the intact region as 1 N (............. 3 ....................... 4 ........) 5. rll-phage strains A-E have point mutations in the rllregion. E.coli K(A) cells are coinfected with one phage that has a deletion and one phage that has a point mutation. The presence of wild-type progeny phage is assessed by the presence (+) or absence (0) of plaques. + 1 2 3 4 5 A + 0 + + + B + + + C + D + 10 + E + +10+ ++ + O Indicate the order of the point mutations in the rll region.

Answer 1

an ave Answer: The answer will be "DEBAC". Explanation Here the E.coli is co-infected ulith phages that have deletions and also phages that have point mutations in all possible combinationg. If the fugo phages have deletion and point mufofions respectively, in different regions of rii, then through different mechanizme like crossing Over befween these two sequences, it can result in the formation of intact all which would help in the proliferation of the phages hence plaques & formed. Here it the E. coliis co-infected with the two phages that have delefion and point mufation respectively in the same region of all, then the phage progeny is not aseen as there is no intact, protein formed that is required for the phage proliferation Chence no plaque formation), no matter in which way crossing over happenis in this case. To know the order of pomp mufation, first look of the delefion sequences and see which among has delated sequences focdards the start of oll, it is 3. Then from the table see which point mutation from A-E When co-bransformed, with 3 would resunt in lack of phages= Dand E, which implies that these point mefafions are coming in the position of the deleted Sequence 3. D is coming before E because 5 whe's co-infecled with E is not forming phages, but co-infected with D is forming pages. Hence for present in the deleted sequencé región of 5 which is not in 3 and D is present in the deleted sequence region of 3 that is nof in 5, and also comes upstream of 5. After 3 and 5, the next portion is deleted in 1, and co-infection of 1 weith B is not forming phoges, Hence B comes after Dand. Erespectively. The next region which is deleted is in 2 followed by 4 and co-infection with A and c respectively foom no colonies. Hence the next two point mifepions after D-E-B are A and C. So, the order of po-mt mufafions is DEBAC 1-5