Monitoring methionine sulfoxide with stereospecific mechanism-based fluorescent sensors

Nat Chem Biol. 2015 May;11(5):332-8. doi: 10.1038/nchembio.1787. Epub 2015 Mar 23.


Methionine can be reversibly oxidized to methionine sulfoxide (MetO) under physiological and pathophysiological conditions, but its use as a redox marker suffers from the lack of tools to detect and quantify MetO within cells. In this work, we created a pair of complementary stereospecific genetically encoded mechanism-based ratiometric fluorescent sensors of MetO by inserting a circularly permuted yellow fluorescent protein between yeast methionine sulfoxide reductases and thioredoxins. The two sensors, respectively named MetSOx and MetROx for their ability to detect S and R forms of MetO, were used for targeted analysis of protein oxidation, regulation and repair as well as for monitoring MetO in bacterial and mammalian cells, analyzing compartment-specific changes in MetO and examining responses to physiological stimuli.

Publication types

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

MeSH terms

  • Escherichia coli / drug effects
  • Fluorescence
  • HEK293 Cells
  • Humans
  • Methionine / analogs & derivatives*
  • Methionine / analysis
  • Methionine / chemistry*
  • Oxidants / pharmacology
  • Oxidation-Reduction
  • Sodium Hypochlorite / pharmacology
  • Stereoisomerism


  • Oxidants
  • Methionine
  • Sodium Hypochlorite
  • methionine sulfoxide