Ag(+)-mediated assembly of 5'-guanosine monophosphate.
Ag(+)-mediated assembly of 5'-guanosine monophosphate.
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DOI：
10.1021/jp908085s
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发表时间：
2010-04-01
期刊：
影响因子：
--
通讯作者：
Petty JT
中科院分区：
文献类型：
--
作者：
Loo K;Degtyareva N;Park J;Sengupta B;Reddish M;Rogers CC;Bryant A;Petty JT
核酸的多晶型形式为新的纳米材料提供了平台，过渡金属阳离子通过与富电子官能团配位而获得了核碱基的替代排列。本文研究了Ag+与5 ′-鸟苷酸（5 ′-GMP）的相互作用。Ag+促进核苷酸堆积和聚集，如通过具有Ag+的5 '-GMP溶液的粘度增加、Ag+对鸟嘌呤的圆二色性响应的放大以及Ag+与鸟嘌呤衍生物之间的放热反应所指示的。等温滴定量热法研究表明，在10 μM 5 '-GMP下开始反应更有利。利用与Ag+与5 '-GMP的反应相关的放热热变化，评估聚集体内的局部结构。基于盐依赖性和与相应核苷的比较，5 '-GMP的双阴离子磷酸盐是Ag+的一个结合位点，尽管这种静电相互作用对总体热变化不是主要贡献。另一个结合位点是核碱基上的N7，如通过用7-脱氮鸟苷的研究所确定的。除了这个结合位点，Ag+还与O 6相关联，如早期的研究从与加合物形成相关的羰基伸缩频率的偏移中推断的。通过核碱基上的这两个结合位点，从量热研究得出的~1 Ag+：核碱基的经验化学计量表明Ag+配位两个核碱基。所提出的结构模型是一个Ag+介导的鸟嘌呤二聚体内的基地堆叠的聚集体。
Polymorphic forms of nucleic acids provide platforms for new nanomaterials, and transition metal cations give access to alternative arrangements of nucleobases by coordinating with electron-rich functional groups. Interaction of Ag+ with 5’-guanosine monophosphate (5’-GMP) is considered in this work. Ag+ promotes nucleotide stacking and aggregation, as indicated by the increased viscosity of 5’-GMP solutions with Ag+, magnification of the circular dichroism response of guanine by Ag+, and exothermic reactions between Ag+ and guanine derivatives. Isothermal titration calorimetry studies show that the reaction is favored starting at 10 μM 5’-GMP. Utilizing the exothermic heat change associated with reaction of Ag+ with 5’-GMP, local structure within the aggregate was assessed. Based on salt dependence and comparison with the corresponding nucleoside, the dianionic phosphate of 5’-GMP is one binding site for Ag+, although this electrostatic interaction is not a dominant contribution to the overall heat change. Another binding site is the N7 on the nucleobase, as determined via studies with 7-deazaguanosine. Besides this binding site, Ag+ also associates with the O6, as earlier studies deduced from the shift in the carbonyl stretching frequency associated with adduct formation. With these two binding sites on the nucleobase, the empirical stoichiometry of ~1 Ag+:nucleobase derived from the calorimetry studies indicates that Ag+ coordinates two nucleobases. The proposed structural model is a Ag+-mediated guanine dimer within a base stacked aggregate.
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影响因子：
14.9
作者：
Cavaluzzi, MJ;Borer, PN
通讯作者：
Borer, PN
影响因子：
2.9
作者：
Kiser, JR;Monk, RW;Petty, JT
通讯作者：
Petty, JT
影响因子：
15
作者：
BELANGERGARIEPY, F;BEAUCHAMP, AL
通讯作者：
BEAUCHAMP, AL
DOI：
10.1039/a702916k
发表时间：
1997-11-07
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
影响因子：
--
作者：
Lippert, B
通讯作者：
Lippert, B
影响因子：
2.9
作者：
Hud, NV;Smith, FW;Feigon, J
通讯作者：
Feigon, J