S-Nitrosylation Induces Structural and Dynamical Changes in a Rhodanese Family Protein

J Mol Biol. 2016 Sep 25;428(19):3737-51. doi: 10.1016/j.jmb.2016.07.010. Epub 2016 Jul 27.


S-Nitrosylation is well established as an important post-translational regulator in protein function and signaling. However, relatively little is known about its structural and dynamical consequences. We have investigated the effects of S-nitrosylation on the rhodanese domain of the Escherichia coli integral membrane protein YgaP by NMR, X-ray crystallography, and mass spectrometry. The results show that the active cysteine in the rhodanese domain of YgaP is subjected to two competing modifications: S-nitrosylation and S-sulfhydration, which are naturally occurring in vivo. It has been observed that in addition to inhibition of the sulfur transfer activity, S-nitrosylation of the active site residue Cys63 causes an increase in slow motion and a displacement of helix 5 due to a weakening of the interaction between the active site and the helix dipole. These findings provide an example of how nitrosative stress can exert action at the atomic level.

Keywords: X-ray crystallography; mass spectrometry; nuclear magnetic resonance (NMR); post-translational modification; rhodanese.

MeSH terms

  • Catalytic Domain
  • Crystallography, X-Ray
  • Cysteine / metabolism
  • Escherichia coli / enzymology*
  • Escherichia coli Proteins / chemistry*
  • Escherichia coli Proteins / metabolism*
  • Magnetic Resonance Spectroscopy
  • Mass Spectrometry
  • Models, Molecular
  • Protein Conformation
  • Protein Processing, Post-Translational*
  • Thiosulfate Sulfurtransferase / chemistry*
  • Thiosulfate Sulfurtransferase / metabolism*


  • Escherichia coli Proteins
  • YgaP protein, E coli
  • Thiosulfate Sulfurtransferase
  • Cysteine