Single-stranded DNA-binding protein that participates in viral DNA replication, formation of concatemers, recombination and repair of double-stranded breaks (PubMed:16807232, PubMed:8617248, PubMed:9079662, PubMed:11222583). Coats the lagging-strand ssDNA as the replication fork advances and stimulates the activities of viral DNA polymerase and primase/helicase (PubMed:8617248). Coordinates simultaneous synthesis of leading- and lagging-strands (PubMed:9651583). Together with DNA primase/helicase, promotes pairing of two homologous DNA molecules containing complementary single-stranded regions and mediates homologous DNA strand exchange (PubMed:8617248). Promotes also the formation of joint molecules (PubMed:8617248, PubMed:9079662). Disrupts loops, hairpins and other secondary structures present on ssDNA to reduce and eliminate pausing of viral DNA polymerase at specific sites during elongation (PubMed:1634538). Homodimer (PubMed:1634538, PubMed:11481454). Interacts (via C-terminus) with the viral DNA polymerase (PubMed:15795374, PubMed:1634539, PubMed:8106511, PubMed:12766155). Interacts with the viral helicase/primase (PubMed:1634539). Part of the replicase complex that includes the DNA polymerase, host thioredoxin, the primase/helicase and the single-stranded DNA binding protein (PubMed:22977246). The acidic C-terminus is involved in modulating the ssDNA binding properties (PubMed:16807232, PubMed:12766155, PubMed:8106511). It is also required for dimer formation and for interactions with the viral DNA polymerase and the helicase (PubMed:16807232, PubMed:12766155, PubMed:8106511). Belongs to the Teseptimavirus single-stranded DNA-binding protein family.