Scripps VIVO scripps research logo

  • Index
  • Log in
  • Home
  • People
  • Organizations
  • Research
  • Events
Search form

Structure and function of the multifunctional DNA-repair enzyme exonuclease-iii

Academic Article
uri icon
  • Overview
  • Identity
  • Additional Document Info
  • View All
scroll to property group menus

Overview

authors

  • Mol, C. D.
  • Kuo, C. F.
  • Thayer, M. M.
  • Cunningham, R. P.
  • Tainer, John

publication date

  • March 1995

journal

  • Nature  Journal

abstract

  • The repair of DNA requires the removal of abasic sites, which are constantly generated in vivo both spontaneously and by enzymatic removal of uracil, and of bases damaged by active oxygen species, alkylating agents and ionizing radiation. The major apurinic/apyrimidinic (AP) DNA-repair endonuclease in Escherichia coli is the multifunctional enzyme exonuclease III, which also exhibits 3'-repair diesterase, 3'-->5' exonuclease, 3'-phosphomonoesterase and ribonuclease activities. We report here the 1.7 A resolution crystal structure of exonuclease III which reveals a 2-fold symmetric, four-layered alpha beta fold with similarities to both deoxyribonuclease I and RNase H. In the ternary complex determined at 2.6 A resolution, Mn2+ and dCMP bind to exonuclease III at one end of the alpha beta-sandwich, in a region dominated by positive electrostatic potential. Residues conserved among AP endonucleases from bacteria to man cluster within this active site and appear to participate in phosphate-bond cleavage at AP sites through a nucleophilic attack facilitated by a single bound metal ion.

subject areas

  • Amino Acid Sequence
  • Computer Graphics
  • Crystallography, X-Ray
  • DNA Repair
  • Deoxycytidine Monophosphate
  • Deoxyribonuclease I
  • Electrochemistry
  • Escherichia coli
  • Exodeoxyribonucleases
  • Humans
  • Manganese
  • Models, Molecular
  • Molecular Sequence Data
  • Protein Conformation
  • Protein Structure, Secondary
  • Ribonuclease H
  • Structure-Activity Relationship
scroll to property group menus

Identity

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/374381a0

PubMed ID

  • 7885481
scroll to property group menus

Additional Document Info

start page

  • 381

end page

  • 386

volume

  • 374

issue

  • 6520

©2021 The Scripps Research Institute | Terms of Use | Powered by VIVO

  • About
  • Contact Us
  • Support