Guerrini Luca, Alvarez-Puebla Ramon A
Department of Physical and Inorganic Chemistry-EMaS, Universitat Rovira I Virgili, Carrer de Marcel∙lí Domingo s/n, 43007 Tarragona, Spain.
ICREA, Passeig Lluís Companys 23, 08010 Barcelona, Spain.
Nanomaterials (Basel). 2021 Jan 27;11(2):326. doi: 10.3390/nano11020326.
Direct, label-free analysis of nucleic acids via surface-enhanced Raman spectroscopy (SERS) has been continuously expanding its range of applications as an intriguing and powerful analytical tool for the structural characterization of diverse DNA structures. Still, interrogation of nucleic acid tertiary structures beyond the canonical double helix often remains challenging. In this work, we report for the first time the structural identification of DNA triplex structures. This class of nucleic acids has been attracting great interest because of their intriguing biological functions and pharmacological potential in gene therapy, and the ability for precisely engineering DNA-based functional nanomaterials. Herein, structural discrimination of the triplex structure against its duplex and tertiary strand counterparts is univocally revealed by recognizing key markers bands in the intrinsic SERS fingerprint. These vibrational features are informative of the base stacking, Hoogsteen hydrogen bonding and sugar-phosphate backbone reorganization associated with the triple helix formation. This work expands the applicability of direct SERS to nucleic acids analysis, with potential impact on fields such as sensing, biology and drug design.
通过表面增强拉曼光谱（SERS）对核酸进行直接、无标记分析，作为一种用于多种DNA结构的结构表征的有趣且强大的分析工具，其应用范围一直在不断扩大。然而，对超出经典双螺旋的核酸三级结构进行研究通常仍然具有挑战性。在这项工作中，我们首次报告了DNA三链体结构的结构鉴定。这类核酸因其在基因治疗中有趣的生物学功能和药理学潜力，以及精确设计基于DNA的功能纳米材料的能力而备受关注。在此，通过识别固有SERS指纹中的关键标记带，明确揭示了三链体结构与其双链和第三条链对应物之间的结构差异。这些振动特征有助于了解与三螺旋形成相关的碱基堆积、Hoogsteen氢键和糖磷酸骨架重组。这项工作扩展了直接SERS在核酸分析中的适用性，对传感、生物学和药物设计等领域具有潜在影响。
