Models for the binary complex of bacteriophage T4 gp59 helicase loading protein: gp32 single-stranded DNA-BINDING protein and ternary complex with pseudo-Y junction DNA.

ABSTRACT: Bacteriophage T4 gp59 helicase assembly protein (gp59) is required for loading of gp41 replicative helicase onto DNA protected by gp32 single-stranded DNA-binding protein. The gp59 protein recognizes branched DNA structures found at replication and recombination sites. Binding of gp32 protein (full-length and deletion constructs) to gp59 protein measured by isothermal titration calorimetry demonstrates that the gp32 protein C-terminal A-domain is essential for protein-protein interaction in the absence of DNA. Sedimentation velocity experiments with gp59 protein and gp32ΔB protein (an N-terminal B-domain deletion) show that these proteins are monomers but form a 1:1 complex with a dissociation constant comparable with that determined by isothermal titration calorimetry. Small angle x-ray s

SUBMITTER: Hinerman JM 

PROVIDER: S-EPMC3365718 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature