Conductance Switching in Single-Peptide Molecules through Interferer Binding

Li-Wen Huang; Yen-Hsun Su; Chao-Cheng Kaun

doi:10.1021/acsomega.8b01229

Conductance Switching in Single-Peptide Molecules through Interferer Binding

ACS Omega. 2018 Aug 15;3(8):9191-9195. doi: 10.1021/acsomega.8b01229. eCollection 2018 Aug 31.

Authors

Li-Wen Huang^{1

2}, Yen-Hsun Su², Chao-Cheng Kaun^{1

3}

Affiliations

¹ Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan, Republic of China.
² Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan, Republic of China.
³ Department of Physics, National Tsing-Hua University, Hsinchu 30013, Taiwan, Republic of China.

Abstract

Detection of bioprocess-interfering metal ions and molecules is important for healthcare, and peptide single-molecule junctions have shown their potential toward sensing these targets efficiently. Using first-principles calculations, we investigate the conductance of Cys-Gly-Cys and cysteamine-Gly-Gly-Cys peptide junctions, and the effect of its change upon copper-ion (Cu²⁺) or bisphenol A (BPA) binding. The calculated conductance of the peptides and the Cu²⁺-peptide complexes agrees well with the experimental data and that of the BPA-bond peptides is further predicted. Our analyses show that the conductance switching mainly comes from the structure deformation of the peptide caused by Cu²⁺ binding or from the new conduction channel added by BPA binding. Our results suggest that the cysteamine-Gly-Gly-Cys junction can recognize Cu²⁺ and BPA better than the Cys-Gly-Cys one does.