The E. coli SufS-SufE sulfur transfer system is more resistant to oxidative stress than IscS-IscU

FEBS Lett. 2012 Nov 16;586(22):4016-22. doi: 10.1016/j.febslet.2012.10.001. Epub 2012 Oct 12.

Abstract

During oxidative stress in Escherichiacoli, the SufABCDSE stress response pathway mediates iron-sulfur (Fe-S) cluster biogenesis rather than the Isc pathway. To determine why the Suf pathway is favored under stress conditions, the stress response SufS-SufE sulfur transfer pathway and the basal housekeeping IscS-IscU pathway were directly compared. We found that SufS-SufE cysteine desulfurase activity is significantly higher than IscS-IscU at physiological cysteine concentrations and after exposure to H(2)O(2). Mass spectrometry analysis demonstrated that IscS-IscU is more susceptible than SufS-SufE to oxidative modification by H(2)O(2). These important results provide biochemical insight into the stress resistance of the Suf pathway.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Biocatalysis / drug effects
  • Carbon-Sulfur Lyases / genetics
  • Carbon-Sulfur Lyases / metabolism*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cysteine / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Hydrogen Peroxide / pharmacology
  • Iron-Sulfur Proteins / genetics
  • Iron-Sulfur Proteins / metabolism*
  • Kinetics
  • Lyases / genetics
  • Lyases / metabolism*
  • Mass Spectrometry
  • Oxidants / pharmacology
  • Oxidation-Reduction
  • Oxidative Stress*
  • Substrate Specificity
  • Sulfur / metabolism*

Substances

  • Carrier Proteins
  • Escherichia coli Proteins
  • Iron-Sulfur Proteins
  • IscU protein, E coli
  • Oxidants
  • Suf E protein, E coli
  • Sulfur
  • Hydrogen Peroxide
  • Lyases
  • Carbon-Sulfur Lyases
  • cysteine desulfurase
  • selenocysteine lyase
  • Cysteine