Fleming Stephen J, Lu Bo, Golovchenko Jene A
Department of Physics, Harvard University, Cambridge, Massachusetts.
Department of Physics, Harvard University, Cambridge, Massachusetts; School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts.
Biophys J. 2017 Jan 24;112(2):368-375. doi: 10.1016/j.bpj.2016.12.007.
We report effective charges and diffusion constants of several different single-stranded DNA oligonucleotides trapped in an MspA nanopore. Nucleotide identity is found to have a substantial influence on effective charges and diffusion constants. These quantities are determined from escape time experiments for a DNA molecule attached to a NeutrAvidin molecule that, unlike the DNA, does not pass through the pore. Correlations are reported between oligonucleotide effective charges and current blockages, and between their diffusion constants and DNA-induced current blockage fluctuations. We also report an unanticipated source of current fluctuations that reflects a discrete blockage current level structure. We posit that this is associated with interactions between the NeutrAvidin molecule and the MspA nanopore.
我们报告了被困在MspA纳米孔中的几种不同单链DNA寡核苷酸的有效电荷和扩散常数。发现核苷酸身份对有效电荷和扩散常数有重大影响。这些量是通过对连接到中性抗生物素蛋白分子上的DNA分子进行逃逸时间实验确定的，与DNA不同，中性抗生物素蛋白分子不会穿过孔。报告了寡核苷酸有效电荷与电流阻断之间以及它们的扩散常数与DNA诱导的电流阻断波动之间的相关性。我们还报告了一个意外的电流波动源，它反映了离散的阻断电流水平结构。我们推测这与中性抗生物素蛋白分子和MspA纳米孔之间的相互作用有关。
