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Tuning Cyclometalated Gold(III) for Cysteine Arylation and Ligand-Directed Bioconjugation.

ABSTRACT: Transition-metal-based approaches to selectively modify proteins hold promise in addressing challenges in chemical biology. Unique bioorthogonal chemistry can be achieved with preformed metal-based compounds; however, their utility in native protein sites within cells remain underdeveloped. Here, we tune the ancillary ligands of cyclometalated gold(III) as a reactive group, and the gold scaffold allows for rapid modification of a desired cysteine residue proximal to the ligand binding site of a target protein. Moreover, evidence for a ligand association mechanism toward C-S bond formation by X-crystallography is established. The observed reactivity of cyclometalated gold(III) enables the rational design of a cysteine-targeted covalent inhibitor of mutant KRAS. This work illustrates the potential of structure-activity relationship studies to tune kinetics of cysteine arylation and rational design of metal-mediated ligand affinity chemistry (MLAC) of native proteins.

SUBMITTER: Gukathasan S

PROVIDER: S-EPMC8711130 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Tuning Cyclometalated Gold(III) for Cysteine Arylation and Ligand-Directed Bioconjugation.

Gukathasan Sailajah S Parkin Sean S Black Esther P EP Awuah Samuel G SG

Inorganic chemistry 20210817 19

Transition-metal-based approaches to selectively modify proteins hold promise in addressing challenges in chemical biology. Unique bioorthogonal chemistry can be achieved with preformed metal-based compounds; however, their utility in native protein sites within cells remain underdeveloped. Here, we tune the ancillary ligands of cyclometalated gold(III) as a reactive group, and the gold scaffold allows for rapid modification of a desired cysteine residue proximal to the ligand binding site of a ...[more]

PMID: 34402302

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