Mustard gas crosslinking of proteins through preferential alkylation of cysteines

by Byrne, Michael Patrick; Broomfield, Clarence A.; Stites, Wesley Eugene

Mustard gas, bis(2-chloroethyl)sulfide, treatment of proteins is shown to generate significant amounts of covalently crosslinked protein dimers. This is due to the preferential alkylation of cysteine residues. Crosslinking does not occur in the model protein staphylococcal nuclease, which has no cysteine residues. Treatment of cysteine-containing mutants of staphylococcal nuclease with this chemical warfare agent did result in crosslinking. However, these dimers are slowly cleaved back to monomers by an unknown mechanism. The alkylation and crosslinking of cysteine-containing proteins by mustard gas may contribute to its toxicity.

Journal
Journal of Protein Chemistry
Volume
15
Issue
2
Year
1996
Start Page
131
ISBN/ISSN
1875-8355; 0277-8033
DOI
10.1007/BF01887394