Burns Jonathan R, Wood James W, Stulz Eugen
Department of Chemistry, University College London, London, United Kingdom.
School of Chemistry & Institute for Life Sciences, University of Southampton, Southampton, United Kingdom.
Front Chem. 2020 Feb 26;8:113. doi: 10.3389/fchem.2020.00113. eCollection 2020.
DNA-based molecular rulers enable scientists to determine important parameters across biology, from the measurement of protein binding interactions, to the study of membrane dynamics in cells. However, existing rulers can suffer from poor nanometre resolution due to the flexible nature of linkers used to tether to the DNA framework. We aimed to overcome this problem using zinc and free-base porphyrin chromophores attached via short and rigid acetylene linkers. This connectivity enables the distance and angle between the porphyrins to be fine-tuned along the DNA scaffold. The porphyrins undergo favorable energy transfer and chiral exciton coupling interactions to act as highly sensitive molecular ruler probes. To validate the system, we monitored the detection of small changes in DNA structure upon intercalation of ethidium bromide. CD spectroscopy showed the porphyrins undergo highly sensitive changes in excitation coupling to facilitate base pair resolution of the novel system.
基于DNA的分子尺使科学家能够确定生物学中的重要参数，从蛋白质结合相互作用的测量到细胞中膜动力学的研究。然而，由于用于连接到DNA框架的接头具有柔性，现有的分子尺可能存在纳米分辨率较差的问题。我们旨在通过经由短而刚性的乙炔接头连接的锌和游离碱卟啉发色团来克服这个问题。这种连接方式能够沿着DNA支架对卟啉之间的距离和角度进行微调。卟啉会发生有利的能量转移和手性激子耦合相互作用，从而充当高度灵敏的分子尺探针。为了验证该系统，我们监测了溴化乙锭插入后DNA结构微小变化的检测情况。圆二色光谱显示，卟啉在激发耦合方面发生了高度灵敏的变化，以促进新系统的碱基对分辨。
