Enhanced translocation of single DNA molecules through alpha-hemolysin nanopores by manipulation of internal charge

Maglia, G., Restrepo, MR., Mikhailova, E. & Bayley, H., 16-Dec-2008, In : Proceedings of the National Academy of Science of the United States of America. 105, 50, p. 19720-19725 6 p.

Research output: Contribution to journalArticleAcademicpeer-review

Both protein and solid-state nanopores are under intense investigation for the analysis of nucleic acids. A crucial advantage of protein nanopores is that site-directed mutagenesis permits precise tuning of their properties. Here, by augmenting the internal positive charge within the alpha-hemolysin pore and varying its distribution, we increase the frequency of translocation of a 92-nt single-stranded DNA through the pore at + 120 mV by approximate to 10-fold over the wild-type protein and dramatically lower the voltage threshold at which translocation occurs, e. g., by 50 mV for 1 event.s(-1).mu M(-1). Further, events in which DNA enters the pore, but is not immediately translocated, are almost eliminated. These experiments provide a basis for improved nucleic acid analysis with protein nanopores, which might be translated to solid-state nanopores by using chemical surface modification.
Original languageEnglish
Pages (from-to)19720-19725
Number of pages6
JournalProceedings of the National Academy of Science of the United States of America
Issue number50
Publication statusPublished - 16-Dec-2008
Externally publishedYes


  • DNA sequencing, electroosmosis, nanopore, protein engineering, single-molecule detection

ID: 36008666