Papillomavirus E1 helicase assembly maintains an asymmetric state in the absence of DNA and nucleotide cofactors.

ABSTRACT: Concerted, stochastic and sequential mechanisms of action have been proposed for different hexameric AAA+ molecular motors. Here we report the crystal structure of the E1 helicase from bovine papillomavirus, where asymmetric assembly is for the first time observed in the absence of nucleotide cofactors and DNA. Surprisingly, the ATP-binding sites adopt specific conformations linked to positional changes in the DNA-binding hairpins, which follow a wave-like trajectory, as observed previously in the E1/DNA/ADP complex. The protein's assembly thus maintains such an asymmetric state in the absence of DNA and nucleotide cofactors, allowing consideration of the E1 helicase action as the propagation of a conformational wave around the protein ring. The data imply that the wave's propagation withi

SUBMITTER: Sanders CM 

PROVIDER: S-EPMC2095799 | biostudies-literature | 2007

REPOSITORIES: biostudies-literature