Publication
The on-line electrochemical tagging (EC-tagging) of cysteine residues in proteins during mass spectrometry is studied to probe the cysteine environment. Benzoquinone probes electrogenerated at a microspray electrode react with the thiol functions of the proteins within a microchannel and the products are analyzed by mass spectrometry. The fundamentals of the technique are discussed, with a focus on the kinetic aspects. The EC-tagging efficiency of the cysteine residues in proteins is used to probe their environment. Experiments with unmodified proteins and their chemically reduced forms highlight the strong effect of the cysteine site reactivity on the tagging efficiencies. This study highlights relevant parameters for such on-line electrochemical derivatization/MS detection strategies.
Jérôme Waser, Durga Prasada Rao Hari, Romain Gaëtan Tessier, Abhaya Kumar Mishra
Jérôme Waser, Romain Gaëtan Tessier, Charlotte Marie Sornay, Raj Kumar Nandi