Structural evidence for an essential Fe-S cluster in the catalytic core domain of DNA polymerase ϵ.

ABSTRACT: DNA polymerase ϵ (Pol ϵ), the major leading-strand DNA polymerase in eukaryotes, has a catalytic subunit (Pol2) and three non-catalytic subunits. The N-terminal half of Pol2 (Pol2CORE) exhibits both polymerase and exonuclease activity. It has been suggested that both the non-catalytic C-terminal domain of Pol2 (with the two cysteine motifs CysA and CysB) and Pol2CORE (with the CysX cysteine motif) are likely to coordinate an Fe-S cluster. Here, we present two new crystal structures of Pol2CORE with an Fe-S cluster bound to the CysX motif, supported by an anomalous signal at that position. Furthermore we show that purified four-subunit Pol ϵ, Pol ϵ CysAMUT (C2111S/C2133S), and Pol ϵ CysBMUT (C2167S/C2181S) all have an Fe-S cluster that is not present in Pol ϵ CysXMUT (C665S/C668S). Pol ϵ Cy

SUBMITTER: Ter Beek J 

PROVIDER: S-EPMC6582351 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature