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Single-nucleotide discrimination in immobilized DNA oligonucleotides with a biological nanopore.

ABSTRACT: 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 (alphaHL), are advantageous because they can be precisely manipulated by genetic modification. Here, we show that the transmembrane beta-barrel of an engineered alphaHL 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.

SUBMITTER: Stoddart D

PROVIDER: S-EPMC2683137 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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Single-nucleotide discrimination in immobilized DNA oligonucleotides with a biological nanopore.

Stoddart David D Heron Andrew J AJ Mikhailova Ellina E Maglia Giovanni G Bayley Hagan H

Proceedings of the National Academy of Sciences of the United States of America 20090420 19

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 (alphaHL), are advantageous because they can be precisely manipulated by genetic modification. Here, we show that the transmembrane beta-barrel of an engineered al ...[more]

PMID: 19380741

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