NMR structure of a vestigial nuclease provides insight into the evolution of functional transitions in viral dsDNA packaging motors.

ABSTRACT: Double-stranded DNA viruses use ATP-powered molecular motors to package their genomic DNA. To ensure efficient genome encapsidation, these motors regulate functional transitions between initiation, translocation, and termination modes. Here, we report structural and biophysical analyses of the C-terminal domain of the bacteriophage phi29 ATPase (CTD) that suggest a structural basis for these functional transitions. Sedimentation experiments show that the inter-domain linker in the full-length protein promotes oligomerization and thus may play a role in assembly of the functional motor. The NMR solution structure of the CTD indicates it is a vestigial nuclease domain that likely evolved from conserved nuclease domains in phage terminases. Despite the loss of nuclease activity, fluorescence

SUBMITTER: Mahler BP 

PROVIDER: S-EPMC7672431 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature