Tulsiyan Kiran Devi, Jena Subhrakant, González-Viegas María, Kar Rajiv K, Biswal Himansu S
School of Chemical Sciences, National Institute of Science Education and Research (NISER), Bhimpur-Padanpur, Via-Jatni, District, Khurda, 752050, Bhubaneswar, India.
Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 400094, India.
ACS Cent Sci. 2021 Oct 27;7(10):1688-1697. doi: 10.1021/acscentsci.1c00768. Epub 2021 Sep 15.
Ribonucleic acid (RNA) is exceedingly sensitive to degradation compared to DNA. The current protocol for storage of purified RNA requires freezing conditions below -20 °C. Recent advancements in biological chemistry have identified amino acid-based ionic liquids as suitable preservation media for RNA, even in the presence of degrading enzymes. However, the mechanistic insight into the interaction between ILs and RNA is unclear. To the best of our knowledge, no attempts are made so far to provide a molecular view. This work aims to establish a detailed understanding of how ILs enable structural stability to RNA sourced from Torula yeast. Herein, we manifest the hypothesis of multimodal binding of IL and its minimal perturbation to the macromolecular structure, with several spectroscopic techniques such as time-resolved fluorescence and fluorescence correlation spectroscopy (FCS) aided with molecular dynamics at microsecond time scales. Relevant structural and thermodynamic details from biophysical experiments confirm that even long-term RNA preservation with ILs is a possible alternative devoid of any structural deformation. These results establish a unifying mechanism of how ILs are maintaining conformational integrity and thermal stability. The atomistic insights are transferable for their potential applications in drug delivery and biomaterials by considering the advantages of having maximum structural retention and minimum toxicity.
与DNA相比，核糖核酸（RNA）对降解极为敏感。目前纯化RNA的储存方案要求在低于-20°C的冷冻条件下保存。生物化学领域的最新进展已确定基于氨基酸的离子液体是RNA的合适保存介质，即使在存在降解酶的情况下也是如此。然而，对于离子液体与RNA之间相互作用的机理尚不清楚。据我们所知，目前尚未有人尝试提供分子层面的见解。这项工作旨在深入了解离子液体如何使源自圆酵母的RNA具有结构稳定性。在此，我们通过诸如时间分辨荧光和荧光相关光谱（FCS）等多种光谱技术，并借助微秒时间尺度的分子动力学，证明了离子液体多模式结合的假设及其对大分子结构的最小扰动。生物物理实验的相关结构和热力学细节证实，即使使用离子液体长期保存RNA也是一种可行的选择，且不会导致任何结构变形。这些结果确立了离子液体维持构象完整性和热稳定性的统一机制。考虑到最大程度保持结构和最小毒性的优势，这些原子层面的见解在药物递送和生物材料领域具有潜在应用价值。
