Sculpting an RNA conformational energy landscape by a methyl group modification - A single-molecule FRET study
Sculpting an RNA conformational energy landscape by a methyl group modification - A single-molecule FRET study
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DOI：
10.1002/anie.200705675
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发表时间：
2008-01-01
影响因子：
16.6
通讯作者：
Nienhaus, G. Ulrich
中科院分区：
文献类型：
--
作者：
Kobitski, Andrei Yu.;Hengesbach, Martin;Nienhaus, G. Ulrich
随机或高斯链是展开的生物聚合物的简单近似。由于缺乏结构信息，我们用高斯链近似U状态，它应该具有最小的残留结构，其平均端到端距离Re由[1] pc e ll rR 2 2 ==，（1）其中lc= 76× 6.3 π 479 π是用经验确定的单个核苷酸的轮廓长度计算的RNA聚合物的轮廓长度。[2]单链RNA的持续长度lp强烈依赖于单价和二价阳离子的浓度。在溶剂的低离子强度下，lp= 21 Ω，[3]并且我们用等式1获得Re= 142 Ω。供体和受体之间的轮廓长度包括连接位点（37 nt）和接头（各约1 nt）之间的长度，对应于1C DA= 39× 6.3 nt = 246 nt。通过用染料之间的轮廓长度重新标度端到端距离Re，我们得到平均染料间
A random, or Gaussian chain is a simple approximation of an unfolded biopolymer. For lack of structural information, we approximate the U state, which is supposed to have minimal residual structure, by a Gaussian chain, for which the average end-to-end distance, Re, is given by [1] pc e ll rR 2 2==,(1) where lc= 76× 6.3 Å≈ 479 Å is the contour length of the RNA polymer calculated with an empirically determined contour length of a single nucleotide.[2] The persistence length, lp, of single-stranded RNA strongly depends on the concentration of monovalent and divalent cations. At low ionic strength of the solvent, lp= 21 Å,[3] and we obtain Re= 142 Å with Equation 1. The contour length between donor and acceptor includes the length between the attachment sites (37 nt) and the linkers (~ 1 nt each), corresponding to lC DA= 39× 6.3 Å= 246 Å. By rescaling the end-to-end distance Re with the contour length between dyes, we obtain the average inter-dye