Question

Briefly, describe the state of the F factor in an Hfr, F+, F', and F- strain of E.coli.

Answer 1

Answere : State of Hfr, F+, F' and F- strain of E.coli.

F+ cell : In most bacteria, conjugation depends upon fertility factor which is present in F+ cells. It is also called donor cell.

F- cell : The fertility factor is absent in F- cell. It is also called recipient cell.

Hfr cell : In Hfr cell, The fertility factor is integrated inti the bacterial chromosomes. It behave like donor cell forming sex pili and undergo conjugation wiyh F- cell. It is called High frequency cell.

F' cell : In F' cell, the fertility factor present as separate circular DNA, carrying some bacterial genes. It also act as donor cell.