Single-nucleotide discrimination in immobilized DNA oligonucleotides with a biological nanopore
Stoddart, David × Heron, Andrew J Mikhailova, Ellina Maglia, Giovanni Bayley, Hagan #
National Academy of Sciences
Proceedings of the National Academy of Sciences of the United States of America vol:106 issue:19 pages:7702-7707
The sequencing of individual DNA strands with nanopores is under investigation as a rapid, low-cost platform in which bases are identified in order as the DNA strand is transported through a pore under an electrical potential. Although the preparation of solid-state nanopores is improving, biological nanopores, such as alpha-hemolysin (alpha HL), are advantageous because they can be precisely manipulated by genetic modification. Here, we show that the transmembrane beta-barrel of an engineered alpha HL pore contains 3 recognition sites that can be used to identify all 4 DNA bases in an immobilized single-stranded DNA molecule, whether they are located in an otherwise homopolymeric DNA strand or in a heteropolymeric strand. The additional steps required to enable nanopore DNA sequencing are outlined.