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Updated: Jan 17, 2026
12:47
Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins
Published on: December 27, 2016
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19F NMR-tags for peptidyl prolyl conformation analysis
George S M Hanson1, Faidra Batsaki1, Teagan L Myerscough1
1EaStChem School of Chemistry, The University of Edinburgh Joseph Black Building, David Brewster Road Edinburgh EH9 3FJ UK chris.coxon@ed.ac.uk.
RSC Chemical Biology
|September 17, 2025
Summary
Fluorinated NMR tags can quantify cis/trans proline isomerism in peptides. Several tags chemoselectively report proline conformation, aiding protein studies.
Area of Science:
- Biochemistry
- Chemical Biology
- Structural Biology
Background:
- Proline cis/trans isomerism is crucial for protein folding and interactions.
- Fluorine-19 NMR (19F NMR) can distinguish cis/trans proline populations.
- Fluorine is not endogenous to proteins and requires chemical tagging.
Purpose of the Study:
- To evaluate various fluorinated NMR tags for proline cis/trans isomerism.
- To assess tag reactivity and accuracy in reporting proline conformation.
- To explore applications in intrinsically disordered proteins and protein mutants.
Main Methods:
- Synthesis and application of cysteine-reactive fluorinated tags.
- 19F NMR analysis of modified proline-containing peptides (e.g., Ac-LPAAC, Ac-LPAAX).
- Chemoselective tagging reactions and assessment of regioisomeric products.
Main Results:
- Several tags (nitrobenzenes, sulfonylpyrimidines, acrylamides) showed chemoselectivity and accurate %cis-Pro reporting.
- Pentafluoropyridine reported %cis-Pro reliably despite non-chemoselectivity.
- 3,4-Difluoronitrobenzene demonstrated protein tagging compatibility with modest reactivity.
Conclusions:
- Fluorinated tags offer a valuable method for quantifying cis/trans proline isomerism.
- Selected tags enable accurate monitoring of proline conformation in peptides and proteins.
- These tools can advance the study of intrinsically disordered proteins and protein function.
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