Visualization of alpha-helices in a 6-angstrom resolution cryoelectron microscopy structure of adenovirus allows refinement of capsid protein assignments.

ABSTRACT: The structure of adenovirus was determined to a resolution of 6 A by cryoelectron microscopy (cryoEM) single-particle image reconstruction. Docking of the hexon and penton base crystal structures into the cryoEM density established that alpha-helices of 10 or more residues are resolved as rods. A difference map was calculated by subtracting a pseudoatomic capsid from the cryoEM reconstruction. The resulting density was analyzed in terms of observed alpha-helices and secondary structure predictions for the additional capsid proteins that currently lack atomic resolution structures (proteins IIIa, VI, VIII, and IX). Protein IIIa, which is predicted to be highly alpha-helical, is assigned to a cluster of helices observed below the penton base on the inner capsid surface. Protein VI is present

SUBMITTER: Saban SD 

PROVIDER: S-EPMC1676273 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature