Site‐Selective Disulfide Modification of Proteins: Expanding Diversity beyond the Proteome

Abstract

The synthetic transformation of polypeptides with molecular accuracy holds great promise for providing functional and structural diversity beyond the proteome. Consequently, the last decade has seen an exponential growth of site‐directed chemistry to install additional features into peptides and proteins even inside living cells. The disulfide rebridging strategy has emerged as a powerful tool for site‐selective modifications since most proteins contain disulfide bonds. In this Review, we present the chemical design, advantages and limitations of the disulfide rebridging reagents, while summarizing their relevance for synthetic customization of functional protein bioconjugates, as well as the resultant impact and advancement for biomedical applications.

Oxetane Grafts Installed Site‐Selectively on Native Disulfides to Enhance Protein Stability and Activity In Vivo

“…During the last years, different approaches have been developed for the covalent tethering of the side chains of natural or non‐canonical amino acids 2. Considering natural residues, cysteine (Cys) has been the residue of choice for stapling through alkylation,3 arylation,4 cycloaddition,4b and disulfide forming reactions both at native5 or engineered6 Cys residues. More recently, nitrogen arylation has also been shown to be a useful strategy for macrocyclization of lysine residues on peptides 7.…”

Synthesis and Applications of Protein/Peptide-Polymer Conjugates

“…Weil et al have comprehensively reviewed and compared the known methods for disulfide bond modification as a route to forming protein, peptide and antibody‐hybrid materials. The pioneering work of Brocchini et al, who employed bis ‐sulfone functional PEG to modify immunotherapeutic protein interferon, was followed by contributions from the groups and Caddick and Baker, who introduced mono‐substituted (MSM) and di‐substituted maleimide (DSM) derivatives as irreversible and reversible linkers respectively.…”

Site-selective protein modification via disulfide rebridging for fast tetrazine/trans-cyclooctene bioconjugation

“…6a,12 However, very few native proteins contain free cysteine residues. 13 Furthermore, thiol-maleimide chemistry easily undergoes the retro-Michael reaction resulting in a maleimide exchange with other reactive thiols present, for example glutathione, under physiological conditions causing off-target effects. 4a Therefore, other methods, which can introduce a tetrazine or TCO group in a site-selective fashion into proteins for subsequent IEDDA reactions are highly desirable to expand the scope of their applications.…”