Terminal alkynes react with active-site cysteine nucleophiles
Ontology highlight
ABSTRACT:
INSTRUMENT(S): LTQ Orbitap Discovery, LTQ Orbitrap Velos, instrument model
ORGANISM(S): Mus Musculus (mouse)
SUBMITTER: 
Patrick Wijten
PROVIDER: PXD000073 | Pride | 2013-08-14
REPOSITORIES: Pride
Publications
On terminal alkynes that can react with active-site cysteine nucleophiles in proteases.
Ekkebus Reggy R van Kasteren Sander I SI Kulathu Yogesh Y Scholten Arjen A Berlin Ilana I Geurink Paul P PP de Jong Annemieke A Goerdayal Soenita S Neefjes Jacques J Heck Albert J R AJ Komander David D Ovaa Huib H
Journal of the American Chemical Society 20130215 8
Active-site directed probes are powerful in studies of enzymatic function. We report an active-site directed probe based on a warhead so far considered unreactive. By replacing the C-terminal carboxylate of ubiquitin (Ub) with an alkyne functionality, a selective reaction with the active-site cysteine residue of de-ubiquitinating enzymes was observed. The resulting product was shown to be a quaternary vinyl thioether, as determined by X-ray crystallography. Proteomic analysis of proteins bound t ...[more]
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