Solution Structure of the C-terminal Domain of A20, the Missing Brick for the Characterization of the Interface between Vaccinia Virus DNA Polymerase and its Processivity Factor

Poxviruses are enveloped viruses with a linear, double-stranded DNA genome. Viral synthesis is achieved by functional polymerase holoenzyme composed of three essential proteins. For vaccinia virus (VACV) these E9, the catalytic subunit, family B polymerase, and heterodimeric processivity factor formed D4 A20. The A20 protein links to subunit. High-resolution structures have been obtained for VACV in complex an N-terminal fragment as well E9. In addition, biochemical studies provided evidence that poxvirus-specific insertion (insert 3) E9 interacts C-terminal residues Here, we provide solution two different constructs containing 304–426, fused at their C-terminus either BAP (Biotin Acceptor Peptide)-tag or short peptide helix insert 3. Together results from titration studies, shed light on molecular interface between subunit component comprises hydrophobic conserved within Chordopoxvirinae subfamily. Finally, constructed HADDOCK model A20304-426-E9 complex, which excellent accordance previous experimental data.