Vicinal thiol group of protein

Vicinal thiol groups of proteins refer to pairs of cysteine thiol (–SH) residues located close together within a protein structure, typically separated by only a few amino acids or spatially adjacent due to folding[5][4]. These vicinal dithiols can undergo reversible oxidation reactions to form intramolecular or intermolecular disulfide bonds, critically contributing to protein structural stability, catalytic activity (as in enzymes such as thioredoxins or peroxiredoxins), and cellular redox regulation[5][4][1][3]. Modification or crosslinking of vicinal thiols is a key redox switch for protein function and signal transduction, and their dysregulation is implicated in conditions such as neurodegenerative disease, ischemia, and protein aggregation disorders[5][4]. Certain reagents, such as phenylarsine oxide, specifically bind vicinal dithiols and are used in redox proteomics to probe thiol status or as tools to study their roles in health and disease[4][5]. However, the term itself does not refer to a single protein or a classic drug target, but rather a form of post-translational modification or motif found within many different proteins, and therefore is not considered a specific therapeutic target[4][5][1].

Other names

Vicinal dithiolprotein dithiolclosely spaced cysteine thiolsvicinal cysteine thiols

Oxidation of vicinal thiols to disulfide bonds; Reversible thiol-disulfide exchange; Redox modulation by drugs or oxidants