Disulfides exchange reactions

Disulfide exchange reactions occur over a broad range of conditions—from acid to basic pH—and in a wide variety of buffer constituents. Most crosslinking reactions involving disulfide exchange are done under physiological conditions or those most appropriate to maintain stability of the protein or other molecule being modified. 

Preparation of Immunotoxin Conjugates via Disulfide Exchange Reactions... 

Simanek el al. investigated the structure dependence of the kinetics of thiol-disulfide exchange reactions.[44] In general, the rate of exchange decreased as the size of the dendrimers increased. Dendrimers with disulfides attached near the core undergo exchange more slowly than dendrimers with disulfides at the periphery. No evidence was found for intramolecular macrocyclization (cooperative) exchange. 

C. Paul, K. Kirschner and G. Haenisch, Anal. Biochem. 101, 442 (1980) determine the deadtime for a stopped-flow apparatus using a disulfide exchange reaction. 

Danieli, B. Giardini, A. Lesma, G. PassareUa, D. Peretto, B. Sacchetti, A. Silvani, A. Pratesi, G. Zunino, F. Thiocolchicine-podophyllotoxin conjugates Dynamic libraries based on disulfide exchange reaction. J. Org. Chem. 2006, 71, 2848-2853. 

Covalent polymers with reversible properties arising from dynamic covalent bonds such as disulfide exchange reaction [47 9], transesterification [50,51], transetherification [52], and boronate ester formation [53] were reported without respect to DCC. These studies should involve DCLs in... 

Fig. 10 Covalent immobilization of ssDNA by thiol/disulfide exchange reaction between disulfide-modified oligonucleotides and mercapto-modified substrates...

These early studies clearly revealed the inherent problems of the chemistry for site-directed formation of unsymmetrical disulfides that has to avoid formation of homodimers. These can result from (i) slow rates of activation of the cysteine peptide, (ii) disproportionation of the activated cysteine species, (in) weak activation and thus slow thiolysis by the second cysteine component and thus its oxidation to the homodimer as well as thiol/ disulfide exchange reactions on the unsymmetrical disulfide present in the reaction media. The latter side reactions are partly controlled by operating in degassed argon-saturated buffers or in organic solvents and preferably under acidic conditions where thiol/disulfide exchange reactions on the nonactivated disulfides, i.e. on the target unsymmetrical cystine peptide occurs at slow rates. 

The first natural sulfhydryl activator of FDPase to be described was cystamine, which at pH 7.5 was found to undergo a disulfide exchange reaction with 2 reactive cysteine residues in the protein (45), leading... 

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