The DNA Radical Code. Resolution of Identity in Dissociations of Trinucleotide Codon Cation Radicals in the Gas Phase

0567582 - ÚOCHB 2024 RIV US eng J - Článek v odborném periodiku
Wan, J. - Brož, Břetislav - Liu, Y. - Huang, S. R. - Marek, Aleš - Tureček, F.
The DNA Radical Code. Resolution of Identity in Dissociations of Trinucleotide Codon Cation Radicals in the Gas Phase.
Journal of the American Society for Mass Spectrometry. Roč. 34, č. 2 (2023), s. 304-319. ISSN 1044-0305. E-ISSN 1879-1123
Grant CEP: GA MŠMT(CZ) LTAUSA19094
Institucionální podpora: RVO:61388963
Klíčová slova: electron transfer dissociation * tandem mass spectrometry * photodissociation action spectroscopy
Obor OECD: Analytical chemistry
Impakt faktor: 3.2, rok: 2022
Způsob publikování: Omezený přístup
https://doi.org/10.1021/jasms.2c00322

Sixty DNA trinucleotide cation radicals covering a large part of the genetic code alphabet were generated by electron transfer in the gas phase, and their chemistry was studied by collision-induced dissociation tandem mass spectrometry and theoretical calculations. The major dissociations involved loss of nucleobase molecules and radicals, backbone cleavage, and cross-ring fragmentations that depended on the nature and position of the nucleobases. Mass identity in dissociations of symmetrical trinucleotide cation radicals of the (XXX+2H)+• and (XYX+2H)+• type was resolved by specific 15N labeling. The specific features of trinucleotide cation radical dissociations involved the dominant formation of d2+ ions, hydrogen atom migrations accompanying the formation of (w2+H)+•, (w2+2H)+, and (d2+2H)+ sequence ions, and cross-ring cleavages in the 3′- and 5′-deoxyribose moieties that depended on the nucleobase type and its position in the ion. Born-Oppenheimer molecular dynamics (BOMD) and density functional theory calculations were used to obtain structures and energies of several cation-radical protomers and conformers for (AAA+2H)+•, (CCC+2H)+•, (GGG+2H)+•, (ACA+2H)+•, and (CAA+2H)+• that were representative of the different types of backbone dissociations. The ion electronic structure, protonation and radical sites, and hydrogen bonding were used to propose reaction mechanisms for the dissociations.
Trvalý link: https://hdl.handle.net/11104/0338826