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Molecular bases of cyclodextrin adapter interactions with engineered protein nanopores.

ABSTRACT: Engineered protein pores have several potential applications in biotechnology: as sensor elements in stochastic detection and ultrarapid DNA sequencing, as nanoreactors to observe single-molecule chemistry, and in the construction of nano- and micro-devices. One important class of pores contains molecular adapters, which provide internal binding sites for small molecules. Mutants of the alpha-hemolysin (alphaHL) pore that bind the adapter beta-cyclodextrin (betaCD) approximately 10(4) times more tightly than the wild type have been obtained. We now use single-channel electrical recording, protein engineering including unnatural amino acid mutagenesis, and high-resolution x-ray crystallography to provide definitive structural information on these engineered protein nanopores in unparalleled detail.

SUBMITTER: Banerjee A

PROVIDER: S-EPMC2889592 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Molecular bases of cyclodextrin adapter interactions with engineered protein nanopores.

Banerjee Arijit A Mikhailova Ellina E Cheley Stephen S Gu Li-Qun LQ Montoya Michelle M Nagaoka Yasuo Y Gouaux Eric E Bayley Hagan H

Proceedings of the National Academy of Sciences of the United States of America 20100416 18

Engineered protein pores have several potential applications in biotechnology: as sensor elements in stochastic detection and ultrarapid DNA sequencing, as nanoreactors to observe single-molecule chemistry, and in the construction of nano- and micro-devices. One important class of pores contains molecular adapters, which provide internal binding sites for small molecules. Mutants of the alpha-hemolysin (alphaHL) pore that bind the adapter beta-cyclodextrin (betaCD) approximately 10(4) times more ...[more]

PMID: 20400691

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