Dissociative multi-photon ionization of isolated uracil and uracil-adenine complexes
نویسندگان
چکیده
منابع مشابه
Dissociative multi-photon ionization of isolated uracil and uracil-adenine complexes
Recent multi-photon ionization (MPI) experiments on uracil revealed a fragment ion at m/z 84 that was proposed as a potential marker for ring opening in the electronically excited neutral molecule. The present MPI measurements on deuterated uracil identify the fragment as C3H4N2O (uracil less CO), a plausible dissociative ionization product from the theoretically predicted open-ring isomer. Equ...
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We have evaluated the NMR shielding tensors for A:T,G:C,A:U in Watson-crick, and U-quartet. We have computed NMR shielding tensors at B31YP level by using 6-31G(d) basis set. We have compute anisotropy and asymmetry in A:T,G:C,A:U and U-quartet. The NMR shielding tensors were calculated using the GIAO method. The natural bonding orbital analysis (NBO) were performed. NBO calculation have been ...
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Multi-photon ionization (MPI) of the RNA base uracil has been studied in the wavelength range 220-270 nm, coinciding with excitation to the S2(ππ*) state. A fragment ion at m/z = 84 was produced by 2-photon absorption at wavelengths ≤232 nm and assigned to C3H4N2O(+) following CO abstraction. This ion has not been observed in alternative dissociative ionization processes (notably electron impac...
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The uracil DNA glycosylase superfamily consists of several distinct families. Family 2 mismatch-specific uracil DNA glycosylase (MUG) from Escherichia coli is known to exhibit glycosylase activity on three mismatched base pairs, T/U, G/U and C/U. Family 1 uracil N-glycosylase (UNG) from E. coli is an extremely efficient enzyme that can remove uracil from any uracil-containing base pairs includi...
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ژورنال
عنوان ژورنال: International Journal of Mass Spectrometry
سال: 2016
ISSN: 1387-3806
DOI: 10.1016/j.ijms.2015.12.006