Solution study of the Escherichia coli DNA polymerase III clamp loader reveals the location of the dynamic ψχ heterodimer

Struct Dyn. 2015 Aug 18;2(5):054701. doi: 10.1063/1.4927407. eCollection 2015 Sep.

Abstract

Several X-ray crystal structures of the E. coli core clamp loader containing the five core (δ', δ, and three truncated γ) subunits have been determined, but they lack the ψ and χ subunits. We report the first solution structure of the complete seven-subunit clamp loader complex using small angle X-ray scattering. This structure not only provides information about the location of the χ and ψ subunits but also provides a model of the dynamic nature of the clamp loader complex.