Site-specific DNA binding by the bacteriophage SP01-encoded type II DNA-binding protein.

Abstract

The bacteriophage SP01 genome encodes a virus‐specific type II DNA‐binding protein, TF1. The bacterial proteins of this ubiquitous and evolutionarily conserved class are thought to bind non‐specifically to DNA. In contrast, the experiments described here demonstrate that TF1 binds to specific sites in SP01 DNA. Several of these sites have been characterized by DNase I ‘footprinting’ and four of them have been shown to overlap strong phage promoters for Bacillus subtilis RNA polymerase holoenzyme. We speculate on the possible structural basis of site‐selective DNA binding by a protein of this class.