Nitrile Imines as Peptide and Oligonucleotide Photo-Cross-Linkers in Gas-Phase Ions

0583028 - MBÚ 2024 RIV US eng J - Článek v odborném periodiku
Wan, J. - Nytka, M. - Qian, H. - Vu, K. - Lemr, Karel - Tureček, F.
Nitrile Imines as Peptide and Oligonucleotide Photo-Cross-Linkers in Gas-Phase Ions.
Journal of the American Society for Mass Spectrometry. Roč. 35, č. 2 (2024), s. 344-356. ISSN 1044-0305. E-ISSN 1879-1123
Institucionální podpora: RVO:61388971
Klíčová slova: 1,3-dipolar cycloaddition * noncovalent interactions * molecular-dynamics * bond formation * linking * dispersion * complexes * efficient * charges * binding
Obor OECD: Microbiology
Impakt faktor: 3.2, rok: 2022
Způsob publikování: Omezený přístup
https://pubs.acs.org/doi/epdf/10.1021/jasms.3c00379

Nitrile imines produced by photodissociation of 2,5-diaryltetrazoles undergo cross-linking reactions with amide groups in peptide-tetrazole (tet-peptide) conjugates and a tet-peptide-dinucleotide complex. Tetrazole photodissociation in gas-phase ions is efficient, achieving ca. 50% conversion with 2 laser pulses at 250 nm. The formation of cross-links was detected by CID-MS3 that showed structure-significant dissociations by loss of side-chain groups and internal peptide segments. The structure and composition of cross-linking products were established by a combination of UV-vis action spectroscopy and cyclic ion mobility mass spectrometry (c-IMS). The experimental absorption bands were found to match the bands calculated for vibronic absorption spectra of nitrile imines and cross-linked hydrazone isomers. The calculated collision cross sections (CCSth) for these ions were related to the matching experimental CCSexp from multipass c-IMS measurements. Loss of N-2 from tet-peptide conjugates was calculated to be a mildly endothermic reaction with Delta H-0 = 80 kJ mol(-1) in the gas phase. The excess energy in the photolytically formed nitrile imine is thought to drive endothermic proton transfer, followed by exothermic cyclization to a sterically accessible peptide amide group. The exothermic nitrile imine reaction with peptide amides is promoted by proton transfer and may involve an initial [3 + 2] cycloaddition followed by cleavage of the oxadiazole intermediate. Nucleophilic groups, such as cysteine thiol, did not compete with the amide cyclization. Nitrile imine cross-linking to 2 '-deoxycytidylguanosine was found to be >80% efficient and highly specific in targeting guanine. The further potential for exploring nitrile-imine cross-linking for biomolecular structure analysis is discussed.
Trvalý link: https://hdl.handle.net/11104/0351649