Structure of Escherichia coli exonuclease VII.

ABSTRACT: Exonuclease VII (ExoVII) is a ubiquitous bacterial nuclease. Encoded by the xseA and xseB genes, ExoVII participates in multiple nucleic acid-dependent pathways including the processing of multicopy single-stranded DNA and the repair of covalent DNA-protein crosslinks (DPCs). Although many biochemical properties of ExoVII have been defined, little is known about its structure/function relationships. Here, we use cryoelectron microscopy (cryoEM) to determine that Escherichia coli ExoVII comprises a highly elongated XseA₄·XseB₂₄ holo-complex. Each XseA subunit dimerizes through a central extended α-helical segment decorated by six XseB subunits and a C-terminal, domain-swapped β-barrel element; two XseA₂·XseB₁₂ subcomplexes fur

SUBMITTER: Liu C 

PROVIDER: S-EPMC10835039 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature