Question 3

(Multiple Choice)

Assume that the gene trpA in an auxotrophic strain of E.coli is located at 27 minutes,whereas the gene pyrE is located at 81 minutes. Present an experimental scheme that would allow you to convert one of the auxotrophic strains to a prototrophic


A)F+ auxotroph × F- wild type
B)Hfr auxotroph × F- wild type
C)F+ wild type × F- auxotroph
D)Hfr wild type × F- auxotroph
E)Hfr auxotroph × F- auxotroph

Answer

D