Given the following map of an E coli chromosome if cells fro

Given the following map of an E. coli chromosome, if cells from a Hfr #1 StrS (a+ b+ c+ d+ e+ f+ g+ h+) strain were mixed with cells from a F- StrR (a- b- c- d- e- f- g- h-) strain, and matings were interrupted after 43 minutes, which genes would NOT have been transferred?

Remember that the arrow shows how DNA is transferred into the another cell.

A)	Genes D and F

30 Hfr 3 12\' Hfra1 2 1 Ilfra5 15 Hfr 2 10\' 10\'

Solution

Strain Order of genes transferred time
Hfr # 1 --------- f,d,c,a,g,b,e,h ------------ 2,12,30

Hfr # 2 --------- g,b,e,h,f,d,c,a ------------ 2,3,8,2,12,30

Hfr # 3 --------- f,d,c,a,g,b,e,h ------------ 12,30,5

Hfr # 4 --------- d,f,h,e,b,g,a,c ------------ 15,5,30

Hfr # 5 --------- c,a,g,b,e,h,f,d ------------ 15,10,10,2,2,3,8

Ans: A). Genes D and F