The structure and assembly mechanism of a novel three-stranded tubulin filament that centers phage DNA.

ABSTRACT: Tubulins are a universally conserved protein superfamily that carry out diverse biological roles by assembling filaments with very different architectures. The underlying basis of this structural diversity is poorly understood. Here, we determine a 7.1 Å cryo-electron microscopy reconstruction of the bacteriophage-encoded PhuZ filament and provide molecular-level insight into its cooperative assembly mechanism. The PhuZ family of tubulins is required to actively center the phage within infected host cells, facilitating efficient phage replication. Our reconstruction and derived model reveal the first example of a three-stranded tubulin filament. We show that the elongated C-terminal tail simultaneously stabilizes both longitudinal and lateral interactions, which in turn define filament arc

SUBMITTER: Zehr EA 

PROVIDER: S-EPMC3999902 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature