A large region of the F plasmid (~33 kb)is called the transfer region (tra)and contains about 40 genes necessary for conjugation.The gene traA codes for the protein pilin that is polymerized to form a pilus,using a number of other tra genes.The pilus is a hollow cylinder whose units disassemble once contact is made in order to "reel in" the recipient cell.What other functions of the tra genes are required for transfer?
A)DNA unwinding,and restriction of contact with F⁺ cells
B)DNA replication enzymes
C)resistance to phage infection
D)integration of F genes into the recipient's chromosome
E)integration of F genes into the recipient's plasmid

Question

Quizplus · Accepted Answer

The tra genes are responsible for many steps involved in conjugation, including the formation of the pilus, but also DNA unwinding to allow for transfer and restriction of contact with F⁺ cells to prevent multiple conjugation events with the same cell. DNA replication enzymes are not necessary for conjugation, and resistance to phage infection and integration into recipient DNA or plasmid are not functions of the tra genes specifically.

A Large Region of the F Plasmid (~33 Kb)is Called