An Amphibious Bi-functional Probe For Protein Chemical Cross-linking.

ABSTRACT: Chemical cross-linking mass spectrometry (CXMS) has emerged as a powerful and well-established method for probing protein structure, conformational dynamics, and protein–protein interactions, particularly in cases where classical high-resolution techniques face intrinsic limitations. The development of new cross-linking reagents with defined reactivity, acti-vation, and compatibility with native conditions remains essential for expanding the scope and reliability of CXMS anal-yses. Here we report the design and synthesis of two novel bis-hypervalent iodine reagents, called Togni cross-linking rea-gents 1 and 2, which function as efficient covalent protein cross-linkers. These reagents feature hypervalent iodide motifs on both termini, enabling intra- and intermolecular cross-link formation. They selectively target aromatic amino acids and cys-teine residues and can be activated either by ascorbic acid or through hydrogen abstraction from thiol groups of cysteines. The performance of both reagents and activation modes is demonstrated on a set of structurally and functionally diverse proteins, including apomyoglobin/holomyoglobin and the small GTPase RHOA. Together, these results establish Togni cross-linking agents as versatile additions to the CXMS toolbox and highlight the potential of bis-hypervalent iodine chemistry for studying protein structure and dynamics under mild aqueous conditions.

INSTRUMENT(S):

ORGANISM(S): Equus Caballus (horse) Homo Sapiens (human)

SUBMITTER: Michael Karpisek  

LAB HEAD: Petr Novak

PROVIDER: PXD074784 | Pride | 2026-07-13

REPOSITORIES: Pride