Molecular Rearrangements Involved in the Capsid Shell Maturation of Bacteriophage

作者:Ionel Alina; Velazquez Muriel Javier A; Luque Daniel; Cuervo Ana; Caston Jose R; Valpuesta Jose M; Martin Benito Jaime; Carrascosa Jose L*
来源:Journal of Biological Chemistry, 2011, 286(1): 234-242.
DOI:10.1074/jbc.M110.187211

摘要

Maturation of dsDNA bacteriophages involves assembling the virus prohead from a limited set of structural components followed by rearrangements required for the stability that is necessary for infecting a host under challenging environmental conditions. Here, we determine the mature capsid structure of T7 at 1 nm resolution by cryo-electron microscopy and compare it with the prohead to reveal the molecular basis of T7 shell maturation. The mature capsid presents an expanded and thinner shell, with a drastic rearrangement of the major protein monomers that increases in their interacting surfaces, in turn resulting in a new bonding lattice. The rearrangements include tilting, in-plane rotation, and radial expansion of the subunits, as well as a relative bending of the A-and P-domains of each subunit. The unique features of this shell transformation, which does not employ the accessory proteins, inserted domains, or molecular interactions observed in other phages, suggest a simple capsid assembling strategy that may have appeared early in the evolution of these viruses.

  • 出版日期2011-1-7