Recombinant Escherichia phage RB69 Gp32 (32)

Function

Single-stranded DNA-binding protein that participates in viral DNA replication, recombination, and repair. Coats the lagging-strand ssDNA as the replication fork advances. Stimulates the activities of viral DNA polymerase and the replicative helicase, probably via its interaction with the helicase assembly factor. Together with the replicative helicase and the helicase assembly factor, promotes pairing of two homologous DNA molecules containing complementary single-stranded regions and mediates homologous DNA strand exchange. Promotes also the formation of joint molecules. mRNA specific autogenous translational repressor

Subunit

Homodimer in the absence of DNA, monomer when binding DNA. Interacts with the DNA helicase assembly protein; a ternary complex between the helicase assembly protein, the single-stranded DNA-binding protein and ssDNA is an obligatory intermediate in the helicase loading mechanism. Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, the primase, the replicative helicase and the helicase assembly factor. Interacts (via C-terminus) with the viral SF1 dDA helicase. Interacts with the viral SF2 UvsW repair helicase

• Borjac J. et al. RNA determinants of specificity of two phylogenetically related single-stranded DNA binding proteins. (1997)
• Borjac J. et al. RNA and protein determinants of autogenous translational control by the Ssb proteins of bacteriophages T4 and RB69. (MAY-)
• Sun S. et al. Structure and enzymatic properties of a chimeric bacteriophage RB69 DNA polymerase and single-stranded DNA binding protein with increased processivity. — Proteins (2006)