62624-73-1Relevant academic research and scientific papers
Method for the rapid detection and molecular characterization of DNA alkylating agents by MALDI-TOF mass spectrometry
Garaguso, Ignazio,Halter, Roman,Krzeminski, Jacek,Amin, Shantu,Borlak, Juergen
, p. 8573 - 8582 (2010)
Metabolic activation of polycyclic aromatic hydrocarbons (PAH) may cause DNA adduct formation. While these are commonly detected by the 32P-postlabeling assay, this method is not informative on the chemical nature of the alkylating agent. Here we report a simple and reliable method that employs MALDI-TOF-MS with 2,5-dihydroxybenzoic acid (DHB) matrix layer (ML) sample preparations for the detection and structural characterization of PAH-DNA adducts. The method involves the enzymatic digestion of DNA to 2′-deoxynucleotides followed by solid phase extraction to remove salt and other contaminants prior to MALDI-MS analysis. By collision induced dissociation (CID) structurally relevant fragments are obtained to permit characterization of the alkylating molecules and the adducted nucleotide. Next to guanosine, adenosine and cytidine adducts formed from reactions with (±)-anti- benzo[a]pyrene-7,8-diol-9,10-epoxide (B[a]PDE) are identified at a sensitivity of 32P-postlabeling assay MALDI-MS only indentified deoxycytidine as well nucleoside and dinucleotides adducts. Therefore, this sensitive method enables molecular specification and characterization of adducted nucleotides and of the alkylating agent, and thus, provides comprehensive information that is beyond the 32P-postlabeling assay.
Covalent Nucleoside Adducts of Benzopyrene 7,8-Diol 9,10-Epoxides: Structural Reinvestigation and Characterization of a Novel Adenosine Adduct on the Ribose Moiety.
Sayer, Jane M.,Chadha, Anju,Agarwal, Shiv K.,Yeh, Herman J. C.,Yagi, Haruhiko,Jerina, Donald M.
, p. 20 - 29 (2007/10/02)
The diastereomeric 7,8-diol 9,10-epoxides metabolically derived from the carcinogenic hydrocarbon benzopyrene react with the purine bases in nucleic acids to alkylate their exocyclic amino groups.The major adducts formed from polyguanylic acid and the enantiomers of the diol epoxide-1 (the diastereomer in which the benzylic 7-hydroxyl group and the epoxide oxygen are cis) have been shown to result from cis opening of the epoxide by the N-2 amino group of guanine, rather than trans opening as had previously reported.Four adducts resulting from alkylation of the exocyclic N-6 amino group of adenosine 5'-monophosphate by racemic diol epoxide-1 have been prepared and characterized.In addition, a major adduct formed from adenosine 5'-monophosphate and (-)-(7R,8S)-diol (9R,10S)-epoxide-1, but not from its (+) enantiomer, has been identified as a product of alkylation of the 2'-hydroxyl group of the sugar.We also report a quantitative reevaluation of the extent and distribution of covalent adduct formation from calf thymus DNA and both diastereomeric benzopyrene-diol epoxides, as well as the identification of the principal DNA adducts formed from the enantiomers of diol epoxide-1.Tentative identification of several new minor adducts formed upon reaction of diol epoxide-2 with denaturated DNA is described.The present results provide additional support for our previously proposed correlation between the signs of the circular dichroism bands of these adducts and their absolute configurations at the N-substituted benzylic carbon atom.
