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Chemical-induced pH-mediated molecular switch.

ABSTRACT: The transmembrane protein ?-hemolysin pore has been used to develop ultrasensitive biosensors, study biomolecular folding and unfolding, investigate covalent and noncovalent bonding interactions, and probe enzyme kinetics. Here, we report that, by addition of ionic liquid tetrakis(hydroxymethyl)phosphonium chloride solution to the ?-hemolysin pore, the ?-hemolysin channel can be controlled open or closed by adjusting the pH of the solution. This approach can be employed to develop a novel molecular switch to regulate molecular transport and should find potential applications as a "smart" drug delivery method.

SUBMITTER: Jayawardhana DA

PROVIDER: S-EPMC3214665 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Chemical-induced pH-mediated molecular switch.

Jayawardhana Dilani A DA Sengupta Mrinal K MK Krishantha D M Milan DM Gupta Jyoti J Armstrong Daniel W DW Guan Xiyun X

Analytical chemistry 20110926 20

The transmembrane protein α-hemolysin pore has been used to develop ultrasensitive biosensors, study biomolecular folding and unfolding, investigate covalent and noncovalent bonding interactions, and probe enzyme kinetics. Here, we report that, by addition of ionic liquid tetrakis(hydroxymethyl)phosphonium chloride solution to the α-hemolysin pore, the α-hemolysin channel can be controlled open or closed by adjusting the pH of the solution. This approach can be employed to develop a novel molecu ...[more]

PMID: 21919492

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