Recognition and discrimination of DNA quadruplexes by acridine-peptide conjugates
作者:James E. Redman、J. M. Granadino-Roldán、James A. Schouten、Sylvain Ladame、Anthony P. Reszka、Stephen Neidle、Shankar Balasubramanian
DOI:10.1039/b814682a
日期:——
We have explored a series of trisubstituted acridine-peptide conjugates for their ability to recognize and discriminate between DNA quadruplexes derived from the human telomere, and the c-kit and N-ras proto-oncogenes. Quadruplex affinity was measured as the peptide sequences were varied, together with their substitution position on the acridine, and the identity of the C-terminus (acid or amide). Surface plasmon resonance measurements revealed that all compounds bound to the human telomeric quadruplex with sub-micromolar affinity. Docking calculations from molecular modelling studies were used to model the effects of substituent orientation and peptide sequence. Modelling and experiment were in agreement that placement of the peptide over the face of the acridine is detrimental to binding affinity. The highest degrees of selectivity were observed towards the N-ras quadruplex by compounds capable of forming simultaneous contacts with their acridine and peptide moieties. The ligands that bound best displayed quadruplex affinities in the 1–5 nM range and at least 10-fold discrimination between the quadruplexes studied.
我们研究了一系列三取代吖啶肽共轭物,以了解它们识别和区分来自人类端粒、c-kit 和 N-ras 原癌基因的 DNA 四联体的能力。随着肽序列的变化、吖啶上的替代位置以及 C 端(酸或酰胺)的特性的变化,四链亲和力也随之变化。表面等离子共振测量显示,所有化合物与人类端粒四联体的结合亲和力都在亚微摩级以下。分子建模研究中的对接计算用于模拟取代基方向和肽序列的影响。建模和实验结果一致表明,将肽置于吖啶面上不利于结合亲和力。能够与吖啶和肽分子同时形成接触的化合物对 N-ras 四联体的选择性最高。结合效果最好的配体显示出 1-5 nM 范围内的四重亲和力,而且所研究的四重之间至少有 10 倍的区分度。