High-Resolution Structure of a Virally Encoded DNA-Translocating Conduit and the Mechanism of DNA Penetration

Abstract

Although ϕX174 DNA pilot protein H is monomeric during procapsid assembly, it forms an oligomeric tube on the host cell surface. Reminiscent of a double-stranded DNA phage tail in form and function, the H tube transports the single-stranded ϕX174 genome across the Escherichia coli cell wall. The 2.4-Å resolution H-tube crystal structure suggests functional and energetic mechanisms that may be common features of DNA transport through virally encoded conduits.