The Myeloablative Drug Busulfan Converts Cysteine to Dehydroalanine and Lanthionine in Redoxins.

ABSTRACT: The myeloablative agent busulfan (1,4-butanediol dimethanesulfonate) is an old drug that is used routinely to eliminate cancerous bone marrow prior to hematopoietic stem cell transplant. The myeloablative activity and systemic toxicity of busulfan have been ascribed to its ability to cross-link DNA. In contrast, here we demonstrate that incubation of busulfan with the thiol redox proteins glutaredoxin or thioredoxin at pH 7.4 and 37 °C results in the formation of putative S-tetrahydrothiophenium adducts at their catalytic Cys residues, followed by β-elimination to yield dehydroalanine. Both proteins contain a second Cys, in their catalytic C-X-X-C motif, which reacts with the dehydroalanine, the initial Cys adduct with busulfan, or the S-tetrahydrothiophenium, to form novel intramolecular

SUBMITTER: Scian M 

PROVIDER: S-EPMC5466068 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature