DNA helicase that stimulates viral DNA replication and recombination. Plays a role in T4 DNA replication initiation by selecting and activating DNA origins. Acts by dissociating and reassociating with the DNA molecule being unwound. Unwinds DNA as a monomer in a 5'-to-3' direction at a rate of 250 bp/s and can efficiently displace proteins from the DNA. ATP + H2O = ADP + H(+) + phosphate Interacts with UvsX and gene 32 protein. To E.coli recD (exonuclease V). Dda (DNA-dependent ATPase) entry