title: A MutS protein-immobilized au electrode for detecting single-base mismatch of DNA.
abstract: A novel electrochemical biosensor was developed to detect gene mutation by using a DNA-mismatch binding protein: MutS from Escherichia coli. The MutS protein was immobilized onto an Au-electrode surface via complex formation between a histidine tag of the MutS protein and a thiol-modified nitrilotriacetic acid chemically adsorbed on the Au-electrode surface. When a target double-stranded DNA having a single-base mismatch was captured by the MutS protein on the electrode, some electrostatic repulsion arose between polyanionic DNA strands and anionic 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. By using this assay, one can detect all types of single-base mismatch and single-base deletion.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka, Japan.
authors.forename: Aishan
authors.initials: A
authors.lastname: Han
authors.forename: Tohru
authors.initials: T
authors.lastname: Takarada
authors.forename: Taiki
authors.initials: T
authors.lastname: Shibata
authors.forename: Masamichi
authors.initials: M
authors.lastname: Nakayama
authors.forename: Mizuo
authors.initials: M
authors.lastname: Maeda
mesh_terms: D020137:Base Pair Mismatch; D015374:Biosensing Techniques; D004247:DNA / Q000737:chemistry / Q000235:genetics*; D004563:Electrochemistry; D004566:Electrodes; D029968:Escherichia coli Proteins / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D051719:MutS DNA Mismatch-Binding Protein / Q000737:chemistry*; D010957:Plasmids
chemical_list: D029968:Escherichia coli Proteins; D006046:Gold; D004247:DNA; D051719:MutS DNA Mismatch-Binding Protein; C497175:MutS protein, E coli