Examination of a Chimeric Bis-Electrophile for Selective DNA-Protein Cross-Linking and Mechlorethamine Reveals an Unknown Source of Nitrogen Mustard Cytotoxicity.

ABSTRACT: DNA-protein cross-links (DPCs) are cytotoxic lesions whose study in cells is complicated by the lack of exogenous agents that produce them selectively over DNA-DNA interstrand cross-links (ICLs). The synthesis and reactivity of a chimeric bis-electrophile (MEBAC) that is comprised of a highly reactive alkylating agent and a lysine selective o-ethynyl benzaldehyde is described. DPC formation in nucleosome core particles (NCPs) by MEBAC is >40-times greater than that of ICLs. Cell viability experiments and the single cell Comet assay are consistent with NCP reactivity. Compared to a nitrogen mustard (mechlorethamine, MCE) MEBAC produces higher DPC yields and lower ICL yields in NCPs and in cells at comparable cytotoxicity. Cell viability experiments show that while DPCs from MEBAC are

SUBMITTER: Jiang X 

PROVIDER: S-EPMC12451994 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature