NMR studies and semi-empirical energy calculations for cyclic ADP-ribose.
NMR studies and semi-empirical energy calculations for cyclic ADP-ribose.
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环状 ADP-核糖的 NMR 研究和半经验能量计算。
DOI：
10.1081/ncn-100105243
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Gani,D
中科院分区：
文献类型：
--
作者：
Rutherford,TJ;Wilkie,J;Vu,CQ;Schnackerz,KD;Jacobson,MK;Gani,D
研究了环adp核糖可能的ph依赖性构象开关。可交换质子的核磁共振信号在低温下被观察到，但没有直接证据表明N-3在中性pH下质子化，这是先前假设的。MNDO计算表明，pH依赖性的31p化学位移变化可归因于腺嘌呤N-1附近的磷酸盐的质子化，而不是由于与质子化的N-3的跨环氢键。
A possible pH-dependent conformational switch was investigated for cyclic ADP-ribose. NMR signals for the exchangeable protons were observed in H2O at low temperature, but there was no direct evidence for the protonation of N-3 at neutral pH that has previously been postulated. MNDO calculations indicated that pH dependent31P chemical shift changes are attributable to protonation of the phosphate adjacent to the N-1 of adenine, and not due to trans-annular hydrogen bonding with a protonated N-3.