Discovery of Heteroaromatic Sulfones As A New Class of Biologically Compatible Thiol-Selective Reagents

Xiaofei Chen, Hanzhi Wu, Chung-Min Park, Thomas H. Poole, Gizem Keceli, Nelmi O. Devarie Baez, Allen W. Tsang, W. Todd Lowther, Leslie B. Poole, S. Bruce King, Ming Xian, and Cristina M. Furdui

ACS Chem. Biol., 2017
DOI: 10.1021/acschembio.7b00444

The selective reaction of chemical reagents with reduced protein thiols is critical to biological research. This reaction is utilized to prevent crosslinking of cysteine-containing peptides in common proteomics workflows and is applied widely in discovery and targeted redox investigations of the mechanisms underlying physiological and pathological processes. However, known and commonly used thiol blocking reagents like iodoacetamide, N-ethylmaleimide and others were found to cross-react with oxidized protein sulfenic acids (-SOH) introducing significant errors in studies employing these reagents. We have investigated and are reporting here a new heteroaromatic alkylsulfone, 4-(5-Methanesulfonyl-[1,2,3,4]tetrazol-1-yl)-phenol (MSTP), as selective and highly reactive -SH blocking reagent compatible with biological applications.