HPLC-ESI-MS/MS Research on DNA Interstrand Cross-Links Formed by 1,3-Bis-(2-chloroethyl)-1- nitrosourea
Bifunctional alkylating agent 1,3-Bis-(2-chloroethyl)-1-nitrosourea (BCNU) is a significant anticancer drug in the clinical treatment of human malignancies. Several lines of evidences indicated that the cytotoxic activity of BCNU was related to their ability of inducing DNA interstrand cross-links (ICLs). In the present work, the formation of the ICLs from the treatment of calf thymus DNA with BCNU was studied with HPLC-ESI-MS/MS analysis and QM/MM computations. Double strand calf thymus DNA was treated with BCNU and digested enzymatically down to the nucleoside level. The hydrolysates were analyzed by HPLC separation followed by electrospray ionization tandem mass spectrometric conformation. The main ICL product, 1-N3-deoxycytidyl-2-N1-deoxyguanosyl-ethane, was characterized by selected reaction monitoring (SRM) mode with ion transitions of m/z 521→m/z 405 (M+H+-dR+) and m/z 521→m/z 289 (M+H+-2dR+). QM/MM computations were carried out with ONIOM method to investigate molecular geometric structure of the DNA double helixes containing various cross-links. A stable structure of the dC(N3)-CH2CH2-dG(N1) ICL was obtained, which was consistent with the result of HPLCESI-MS/MS analysis.
Bifunctional alkylating agents DNA Cross-links BCNU LC-ESI-MS/MS
Bao-Qing Bai Li-Jiao Zhao Ru-Gang Zhong
College of Life Science and Bioengineering Beijing University of Technology Beijing 100124,China
国际会议
北京
英文
1-4
2009-06-11（万方平台首次上网日期，不代表论文的发表时间）