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Protein sensing with engineered protein nanopores.

ABSTRACT: The use of nanopores is a powerful new frontier in single-molecule sciences. Nanopores have been used effectively in exploring various biophysical features of small polypeptides and proteins, such as their folding state and structure, ligand interactions, and enzymatic activity. In particular, the ?-hemolysin (?HL) protein pore has been used extensively for the detection, characterization, and analysis of polypeptides because this protein nanopore is highly robust, versatile, and tractable under various experimental conditions. Inspired by the mechanisms of protein translocation across the outer membrane translocases of mitochondria, we have shown the ability to use nanopore-probe techniques in controlling a single protein using engineered ?HL pores. Here, we provide a detailed protocol for the preparation of ?HL protein nanopores. Moreover, we demonstrate that placing attractive electrostatic traps is instrumental in tackling single-molecule stochastic sensing of folded proteins.

SUBMITTER: Mohammad MM

PROVIDER: S-EPMC3708658 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Protein sensing with engineered protein nanopores.

Mohammad Mohammad M MM Movileanu Liviu L

Methods in molecular biology (Clifton, N.J.) 20120101

The use of nanopores is a powerful new frontier in single-molecule sciences. Nanopores have been used effectively in exploring various biophysical features of small polypeptides and proteins, such as their folding state and structure, ligand interactions, and enzymatic activity. In particular, the α-hemolysin (αHL) protein pore has been used extensively for the detection, characterization, and analysis of polypeptides because this protein nanopore is highly robust, versatile, and tractable under ...[more]

PMID: 22528256

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