Gene mutation assay using a MutS protein-modified electrode.

Aishan Han; Taiki Shibata; Tohru Takarada; Mizuo Maeda

doi:10.1093/nass/2.1.287

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Gene mutation assay using a MutS protein-modified electrode.

Aishan Han·Taiki Shibata·Tohru Takarada·Mizuo Maeda

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Abstract

A novel electrochemical biosensor for gene mutation detection was developed using a DNA mismatch recognizing protein MutS from E. coli. The MutS protein was immobilized onto an Au electrode by coordination of His-tag at its C-terminus to vacant sites of Ni(II)-nitrilotriacetato complex attached to the surface of electrode. When a target DNA duplex having a mismatch site was captured by the MutS protein on the electrode, the electrostatic repulsion arose between polyanionic DNA duplexes and negatively-charged ferrocyanide/ferricyanide redox couple ions. Consequently, their redox peak currents on a cyclic voltammogram with the Au electrode drastically decreased depending on the concentration of the target DNA according to the redox couple-mediated artificial ion-channel principle. Using this assay, we could detect GT mismatch and deletion mutation in the double-stranded DNA.

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Adenosine Triphosphatases Bacterial Proteins DNA-Binding Proteins Electrodes Escherichia coli Proteins MutS DNA Mismatch-Binding Protein Mutation Journal Article

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Aishan Han, Taiki Shibata, Tohru Takarada, Mizuo Maeda. 2002. Gene mutation assay using a MutS protein-modified electrode.. https://doi.org/10.1093/nass%2F2.1.287

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