Gas-Phase Fragmentation of Long-Lived Cysteine Radical Cations Formed Via NO Loss from Protonated S-Nitrosocysteine
Victor Ryzhov, Adrian KY Lam, Richard AJ O'Hair
JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY | AMER CHEMICAL SOC | Published : 2009
In this work, we describe two different methods for generating protonated S-nitrosocysteine in the gas phase. The first method involves a gas-phase reaction of protonated cysteine with t-butylnitrite, while the second method uses a solution-based transnitrosylation reaction of cysteine with S-nitrosoglutathione followed by transfer of the resulting S-nitrosocysteine into the gas phase by electrospray ionization mass spectrometry (ESI-MS). Independent of the way it was formed, protonated S-nitrosocysteine readily fragments via bond homolysis to form a long-lived radical cation of cysteine (Cys(*+)), which fragments under collision-induced dissociation (CID) conditions via losses in the follow..View full abstract
The authors thank the ARC for financial Support via the ARC Centre of Excellence in Free Radical Chemistry and Biotechnology. The authors gratefully acknowledge the generous allocation of computing time from both the Victorian Institute for Chemical Science High Performance Computing Facility and the Victorian Partnership for Advanced Computing. The authors thank the ARC and VICS for funding of the LTQ-FT MS instrument. AKYL acknowledges the award of a Melbourne Research Scholarship from The University of Melbourne. VR acknowledges the support from Northern Illinois University and thanks RAJO and The University of Melbourne for research opportunities during his sabbatical leave.