The role of the iron-sulfur cluster in Escherichia coli endonuclease III. A resonance Raman study

J Biol Chem. 1992 Aug 15;267(23):16135-7.

Abstract

Resonance Raman spectroscopy has been used to investigate the function and properties of the iron-sulfur cluster in Escherichia coli endonuclease III. Resonance Raman spectra in the Fe-S stretching region are indicative of a [4Fe-4S]2+ cluster with complete cysteinyl sulfur coordination, and vibrational assignments are made by analogy with bacterial ferredoxins. Minor changes in the vibrational frequencies of the modes primarily involving Fe-S(Cys) stretching accompany the binding of the inhibitor thymine glycol or an oligonucleotide containing a reduced apyrimidinic site. These changes are consistent with perturbation of the orientation of the ligating cysteinyl residues and rule out the possibility that the [4Fe-4S] cluster is directly involved with substrate or inhibitor binding. It is concluded that a structural role is most likely for the [4Fe-4S] cluster in endonuclease III.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • Binding Sites
  • Deoxyribonuclease (Pyrimidine Dimer)
  • Endodeoxyribonucleases / chemistry
  • Endodeoxyribonucleases / metabolism*
  • Escherichia coli / enzymology*
  • Escherichia coli Proteins*
  • Iron-Sulfur Proteins / chemistry
  • Iron-Sulfur Proteins / metabolism*
  • Molecular Sequence Data
  • Oligodeoxyribonucleotides / chemical synthesis
  • Oligodeoxyribonucleotides / metabolism*
  • Spectrum Analysis, Raman / methods
  • Substrate Specificity
  • Thermodynamics

Substances

  • Escherichia coli Proteins
  • Iron-Sulfur Proteins
  • Oligodeoxyribonucleotides
  • Endodeoxyribonucleases
  • Deoxyribonuclease (Pyrimidine Dimer)
  • NTH protein, E coli