Thiol-disulfide interchange

Thiol—Disulfide Interchange Reactions. The interchange between thiols and disulfides has been reviewed (50). This reaction is base-catalyzed. It involves the nucleophihc attack of a thiolate ion on a disulfide. This is shown in equations 35, 36, and 37. 

Keire, D.A., Strauss, E., Guo, W., Noszal, B., Rabenstein, D.L. Kinetics and equilibria of thiol/disulfide interchange reactions of selected biological thiols and related molecules with oxidized glutathione. J. Org. Chem. 1992, 57, 123-127. 

Shaked, Z. Szajewski, R. R Whitesides, G. M. Rates of thiol-disulfide interchange reactions involving proteins and kinetic measurements of thiol pKa values. Biochemistry 1980,19,4156-4166. 

This method is of use in thiol-disulfide interchanges and when using two-protonic-state electrophiles. ... 

Racemic thioglycerol (3-sulfanylpropane-l,2-diol) was used for the attachment of two lipid chains via ester bond formation with the hydroxy groups 82 while the free thiol group serves for selective cross-linking to other molecules via disulfide or sulfide bonds utilizing mild thiol-disulfide interchange or thiol addition reactions (Scheme 15).[163,164,167]... 

Further structure-activity relationship (S AR) analyses of other cytoprotective enzyme inducers revealed the fact that all inducers can react with thiol/disulfide groups by alkylation, oxidoreduction, or thiol-disulfide interchange [Dinkova-Kostova and Talalay, 1999]. In fact, the capability of enzyme inducers to induce cytoprotective enzymes is well correlated with their reactivity with thiols. These results suggested a cellular sensor of inducers with highly reactive sulfhydryl groups, possibly reactive thiols in cysteine residues of a sensor protein. Nevertheless, the initial search for the sensor protein by using radioactively labeled inducers was not successful due to the abundance of thiol groups presented in many proteins in cells [Holtzclaw et al., 2004]. The molecular mechanism by which cytoprotective enzymes are induced remained to be elucidated. 

S. T. Kelly and A. L. Zydney, Effects of intermolecular thiol-disulfide interchange reactions on BSA fouling during microfiltration, Biotech. Bioeng. 1994, 44(8), 972-982. 

In a classic study on bovine pancreatic ribonuclease A at 90°C and pH conditions relevant for catalysis, irreversible deactivation behavior was found to be a function of pH (Zale, 1986) at pH 4, enzyme inactivation is caused mainly by hydrolysis of peptide bonds at aspartic acid residues as well as deamidation of asparagine and/or glutamine residues, whereas at pH 6-8, enzyme inactivation is caused mainly by thiol-disulfide interchange but also by fi-elimination of cystine residues, and deamidation of asparagine and/or glutamine residues. 

Cech, T. R. (1990). Self-splicing of group I introns. Annu. Rev. Biochem. 59, 543—568. Cohen, S. B., and Cech, T. R. (2001). Engineering disulfide cross-links in RNA using thiol-disulfide interchange chemistry. Cun. Protoc. Nucleic Acid Chem. Chapter 5, Unit 5 1. 

Szajewski RP, Whitesides GM (1980) Rate constants and equilibrium constants for thiol-disulfide interchange reactions involving oxidized glutathione. J Am Chem Soc 102 2011-2026... 

Fio. 8. (A) Hypothetical transition state in the electrophilic catalysis of thiol-di-suliide interchange. (B) General acid-base catalysis of thiol-disulfide interchange by a hypothetical amino group. 

Brocklehurst, K. (1996b) Covalent Chromatography by Thiol-Disulfide Interchange Using Solid-Phase Alkyl 2-Pyridyl Disulfides, in Proteins Labfax (Price, N.C., Ed.), BIOS, Oxford. 

Honk J, Whitesides GM. Structure-Reactivity Relations for Thiol-Disulfide Interchange. J. Am. Chem. Soc. 1987 109 6825-6836. 

We have developed several new dithiol reagents for rapid reduction of disulfide groups (2-6). These dithiol reagents reduce disulfide bonds by the mechanism of thiol-disulfide interchange (Eq 1). 

The cystine residues, because they may act as cross-linkages between protein chains, have been studied more closely than other residues in keratin. Burley s (1956a) use of the concept of thiol-disulfide interchange to explain the effects of chemical modification on the physical properties of wool fibers has stimulated further work on cysteine and cystine residues. 

Zahn et al (1960) have suggested that lanthionine may be an inevitable side product of thiol-disulfide interchange reactions involving cysteine and... 

Equilibration of wool with aqueous urea or LiBr, treatments which would be expected to facilitate chain movement and hence also thiol-disulfide interchange, increases the strain at the transition point between the yield and post-yield regions of the stress-strain curves (Crewther, 1965c). 

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