A Cut above the Rest: Characterization of the Assembly of a Large Viral Icosahedral Capsid.

ABSTRACT: The head of Salmonella virus SPN3US is composed of ~50 different proteins and is unusual because within its packaged genome there is a mass (>40 MDa) of ejection or E proteins that enter the Salmonella cell. The assembly mechanisms of this complex structure are poorly understood. Previous studies showed that eight proteins in the mature SPN3US head had been cleaved by the prohead protease. In this study, we present the characterization of SPN3US prohead protease mutants using transmission electron microscopy and mass spectrometry. In the absence of the prohead protease, SPN3US head formation was severely impeded and proheads accumulated on the Salmonella inner membrane. This impediment is indicative of proteolysis being necessary for the release and subsequent DNA pack

SUBMITTER: Reilly ER 

PROVIDER: S-EPMC7411985 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature