Tuesday, December 11, 2018

A Chemoproteomic Strategy for Direct and Proteome-wide Covalent Inhibitor Target-site Identification

Christopher Michael BrowneBaishan JiangScott B FicarroZainab M DoctorJared Lee JohnsonJoseph D CardSindhu Carmen SivakumarenWilliam M AlexanderTomer YaronCharles Joseph MurphyNicholas P KwiatkowskiTinghu ZhangLewis C. CantleyNathanael S Gray, and Jarrod A. Marto

Journal of the American Chemical Society 2018
DOI: 10.1021/jacs.8b07911

Despite recent clinical successes for irreversible drugs, potential toxicities mediated by unpredictable modification of off-target cysteines represents a major hurdle for expansion of covalent drug programs. Understanding the proteome-wide binding profile of covalent inhibitors can significantly accelerate their development; however, current mass spectrometry strategies typically do not provide a direct, amino acid level readout of covalent activity for complex, selective inhibitors. Here we report the development of CITe-Id, a novel chemoproteomic approach that employs covalent pharmacologic inhibitors as enrichment reagents in combination with an optimized proteomic platform to directly quantify dose-dependent binding at cysteine-thiols across the proteome. CITe-Id analysis of our irreversible CDK inhibitor THZ1 identified dose-dependent covalent modification of several unexpected kinases, including a previously unannotated cysteine (C840) on the understudied kinase PKN3. These data streamlined our development of JZ128 as a new selective covalent inhibitor of PKN3. Using JZ128 as a probe compound, we identified novel potential PKN3 substrates, thus offering an initial molecular view of PKN3 cellular activity. CITe-Id provides a powerful complement to current chemoproteomic platforms to characterize the selectivity of covalent inhibitors, identify new, pharmacologically-addressable cysteine-thiols, and inform structure-based drug design programs.

Covalent drug discovery using sulfur(VI) fluoride exchange warheads

Huang Huang, Lyn H. Jones Expert Opinion on Drug Discovery , 2023 https://doi.org/10.1080/17460441.2023.2218642 Covalent drug discovery has ...