The recognition sequences of N proteins of the toxin-converting lambdoid phages: a comparative approach.

抄録

In the N antitermination system of bacteriophage lambda and related phages, the BoxB of the nut site interacts with the N protein to form an antitermination complex. Arginine-rich sequences in the N-proximal region of these proteins in phage lambda, P22 and P21 have been assigned as the recognition sequences of these phages. An arginine-rich motif very similar to that of P22 N protein has been found in the N protein of phage HK97 and the toxin-converting phages 933W and H-19B, which we suggest to be the recognition sequence of these N proteins because these three phages have a BoxB loop sequence identical with that of P22. We also found a slightly different, but similarly located arginine-rich sequence in phage VT2-Sa N protein, which we suggest is the recognition sequence of the N protein for this phage. This is consistent with the fact that its BoxB loop is different from the other three phages.