Proton Transfer Accompanied by the Oxidation of Adenosine

Cited 0 time in webofscience Cited 0 time in scopus
51 Viewed 11 Downloaded
Title
Proton Transfer Accompanied by the Oxidation of Adenosine
Author(s)
Jungkweon Choi; Sachiko Tojo; Doo-Sik Ahn; Mamoru Fujitsuka; Shunichi Miyamoto; Kazuo Kobayashi; Hyotcherl Ihee; Tetsuro Majima
Publication Date
2019-06
Journal
CHEMISTRY-A EUROPEAN JOURNAL, v.25, no.32, pp.7711 - 7718
Publisher
WILEY-V C H VERLAG GMBH
Abstract
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Despite numerous experimental and theoretical studies, the proton transfer accompanying the oxidation of 2′-deoxyadenosine 5′-monophosphate 2’-deoxyadenosine 5’-monophosphate (5’-dAMP, A) is still under debate. To address this issue, we have investigated the oxidation of A in acidic and neutral solutions by using transient absorption (TA) and time-resolved resonance Raman (TR 3 ) spectroscopic methods in combination with pulse radiolysis. The steady-state Raman signal of A was significantly affected by the solution pH, but not by the concentration of adenosine (2–50 mm). More specifically, the A in acidic and neutral solutions exists in its protonated (AH + (N1+H + )) and neutral (A) forms, respectively. On the one hand, the TA spectral changes observed at neutral pH revealed that the radical cation (A .+ ) generated by pulse radiolysis is rapidly converted into A . (N6−H) through the loss of an imino proton from N6. In contrast, at acidic pH (<4), AH .2+ (N1+H + ) generated by pulse radiolysis of AH + (N1+H + ) does not undergo the deprotonation process owing to the pK a value of AH .2+ (N1+H + ), which is higher than the solution pH. Furthermore, the results presented in this study have demonstrated that A, AH + (N1+H + ), and their radical species exist as monomers in the concentration range of 2–50 mm. Compared with the Raman bands of AH + (N1+H + ), the TR 3 bands of AH .2+ (N1+H + ) are significantly down-shifted, indicating a decrease in the bond order of the pyrimidine and imidazole rings due to the resonance structure of AH .2+ (N1+H + ). Meanwhile, A . (N6−H) does not show a Raman band corresponding to the pyrimidine+NH 2 scissoring vibration due to diprotonation at the N6 position. These results support the final products generated by the oxidation of adenosine in acidic and neutral solutions being AH .2+ (N1+H + ) and A . (N6−H), respectively
URI
https://pr.ibs.re.kr/handle/8788114/5967
ISSN
0947-6539
Appears in Collections:
Center for Nanomaterials and Chemical Reactions(나노물질 및 화학반응 연구단) > Journal Papers (저널논문)
Files in This Item:
Chem. Eur.J.2019, 25,7711–7718.pdfDownload

qrcode

  • facebook

    twitter

  • Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
해당 아이템을 이메일로 공유하기 원하시면 인증을 거치시기 바랍니다.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse