Chemical Tools for Probing Cysteine Sulfenation and Sulfination Redox Biology

PROJECT SUMMARY
Post-translational changes in the redox state of cysteine residues can rapidly and reversibly alter protein function,
modulating biological processes and drug pharmacology. During the last funding period, our lab reported several
innovations in organosulfur chemistry, small-molecule tools, and computational methods for proteomic analysis
that dramatically improved selectivity, cellular application, and site-specific quantitation of the cysteine redoxome
(J. Am. Chem. Soc., 2017; Nat. Chem. Biol., 2018; Nat. Chem., 2021; Nat. Comm., 2022). Application of these
chemoproteomic methods has contributed to meaningful discovery of new paradigms in redox biology (Nat. Cell
Biol., 2019; Cell Metab., 2019; Blood Adv., 2020; Nat. Comm., 2021; Redox Biol., 2021 & 2022; Proc. Natl. Acad.
Sci., 2022) and raise interesting new questions about the links between the cellular redox landscape, molecular
thiol-based redox switches, and the emerging field of redox medicine. Herein, the following three Specific Aims
are proposed: Development and application of 1) chemical methods to address spatiotemporal control in redox
signaling; 2) genetic incorporation of oxidized cysteine in proteins to pinpoint molecular mechanisms underlying
thiol-based redox regulation; and 3) nucleophile-fragment libraries to discover covalent ligands that target redox-
regulated proteins in the cysteinome. Strong preliminary data demonstrate that studies proposed herein are both
promising and feasible in our hands. Deliverables resulting from these studies include: 1) valuable new chemical
biology approaches to understand fundamental mechanisms in thiol-based redox signaling, and 2) novel chem-
ical matter that can be mined as a source of small-molecule probes and as starting points for drug discovery.

Grant Number: 5R01GM102187-12
NIH Institute/Center: NIH
Principal Investigator: Kate Carroll