Recognizing a Single Base in an Individual DNA Strand: A Step Toward DNA Sequencing in Nanopores† Academic Article uri icon

abstract

  • There has been an intriguing suggestion that Staphylococcus aureus α-hemolysin (α-HL), a stable heptameric transmembrane protein pore,[1] may be of use as the sensor element in a rapid, pore-mediated, single-molecule DNA sequencing process.[2] Although there remain several requirements that must be met before such a process can be realized,[2a, 3] the most fundamental concern has been whether α-HL, or any other natural or manmade nanopore structure,[4] is capable of recognizing DNA with single nucleobase resolution. We have probed the nucleobase resolution capacity of α-HL by threading and holding a given strand of single-stranded (ss-) DNA inside the α-HL pore in the form of a single α-HL· DNA pseudorotaxane.[5] By using block copolymers of DNA and homopolymeric strands with position-specific single nucleotide substitutions, we have found that a single adenine …

publication date

  • January 1, 2005