Sterk H, Kopp H, Esterbauer H
Z Naturforsch C Biosci. 1979 Aug;34(7-8):503-7.
Nucleosides and nucleotides have been investigated by means of the spin-lattice-relaxationtime T1, the measurements carried out in CDCl3 on the nucleosides adenosine (A), uridine (U) and inosine (I) indicate that the strength of H-bonding is highest in the basepair (A)--(U). The systems (A)--(A), (U)--(U), (I)--(A) and (I)--(U) however, show only a low tendency to associate. Plotting the spin-lattice-relaxationtime, of the nucleotide protons in fragments (mol weight below 40,000) originated from DNA or RNA, against increasing temperature gives a curve with a sigmoide shape and a Tm value of 80 degrees C. The average of the activation energy for the H-bonding is 18.02 KJ/mol. The investigations clearly show that the spin-lattice-relaxationtime measurements open first of all a new method for research on H-bonding, secondly it is even in the case of nucleosides and oligonucleotides, where most of the common methods fail, a way to get information about H-bonding effects.
已通过自旋晶格弛豫时间T1对核苷和核苷酸进行了研究，在CDCl3中对核苷腺苷（A）、尿苷（U）和肌苷（I）进行的测量表明，碱基对（A）-（U）中的氢键强度最高。然而，（A）-（A）、（U）-（U）、（I）-（A）和（I）-（U）体系仅表现出较低的缔合倾向。将源自DNA或RNA的片段（分子量低于40,000）中核苷酸质子的自旋晶格弛豫时间与温度升高作图，得到一条S形曲线，Tm值为80℃。氢键的平均活化能为18.02kJ/mol。这些研究清楚地表明，自旋晶格弛豫时间测量首先开辟了一种研究氢键的新方法，其次，即使在大多数常用方法失效的核苷和寡核苷酸的情况下，它也是一种获取有关氢键效应信息的途径。
