Single-stranded DNA binding protein required for the elongation during viral DNA replication by strand displacement. Displaced viral DNA strands are transiently coated with the ssDNA-binding protein and therefore protected againt nucleases. The latter is then probably removed by the replisome that performs lagging strand synthesis or during the events that lead up to the recombination process. Has helix-destabilizing activity since it removes secondary structure from the ssDNA in replicative intermediates. Monomer. Belongs to the phi29likevirus single-strand-binding protein family.