气候变化领域集成服务门户(CCPortal): Intrinsic electronic conductivity of individual atomically resolved amyloid crystals reveals micrometer-long hole hopping via tyrosines

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DOI	10.1073/pnas.2014139118
	Intrinsic electronic conductivity of individual atomically resolved amyloid crystals reveals micrometer-long hole hopping via tyrosines
	Shipps C.; Ray Kelly H.; Dahl P.J.; Yi S.M.; Vu D.; Boyer D.; Glynn C.; Sawaya M.R.; Eisenberg D.; Batista V.S.; Malvankar N.S.
发表日期	2021
ISSN	00278424
卷号	118 期号:2
英文摘要	Proteins are commonly known to transfer electrons over distances limited to a few nanometers. However, many biological processes require electron transport over far longer distances. For example, soil and sediment bacteria transport electrons, over hundreds of micrometers to even centimeters, via putative filamentous proteins rich in aromatic residues. However, measurements of true protein conductivity have been hampered by artifacts due to large contact resistances between proteins and electrodes. Using individual amyloid protein crystals with atomic-resolution structures as a model system, we perform contact-free measurements of intrinsic electronic conductivity using a four-electrode approach. We find hole transport through micrometer-long stacked tyrosines at physiologically relevant potentials. Notably, the transport rate through tyrosines (105 s−1) is comparable to cytochromes. Our studies therefore show that amyloid proteins can efficiently transport charges, under ordinary thermal conditions, without any need for redox-active metal cofactors, large driving force, or photosensitizers to generate a high oxidation state for charge injection. By measuring conductivity as a function of molecular length, voltage, and temperature, while eliminating the dominant contribution of contact resistances, we show that a multistep hopping mechanism (composed of multiple tunneling steps), not single-step tunneling, explains the measured conductivity. Combined experimental and computational studies reveal that proton-coupled electron transfer confers conductivity; both the energetics of the proton acceptor, a neighboring glutamine, and its proximity to tyrosine influence the hole transport rate through a proton rocking mechanism. Surprisingly, conductivity increases 200-fold upon cooling due to higher availability of the proton acceptor by increased hydrogen bonding. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Amyloids; Electron transport; Molecular dynamics; Protein electronics; Proton-coupled electron transfer
语种	英语
scopus关键词	amyloid protein; nanowire; tyrosine; Article; atomic force microscopy; beta sheet; controlled study; crystal; density functional theory; deprotonation; dielectric constant; electric conductivity; electric field; electric resistance; electrochemical analysis; electron transport; hydrogen bond; hydrophobicity; impedance spectroscopy; ion conductance; molecular dynamics; oxidation reduction potential; polarization; priority journal; process optimization; protein conformation; protein interaction; protein localization; protein stability; proton transport; protonation; thermodynamics
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/181068
作者单位	Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06510, United States; Microbial Sciences Institute, Yale University, West Haven, CT 06516, United States; Department of Chemistry, Yale University, New Haven, CT 06511, United States; HHMI, University of California, Los Angeles, CA 90095, United States; Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, United States; Department of Biological Chemistry, University of California, Los Angeles, CA 90095, United States; Molecular Biology Institute, University of California, Los Angeles, CA 90095, United States; University of California, Los Angeles-Department of Energy, Institute for Genomics and Proteomics, University of California, Los Angeles, CA 90095, United States
推荐引用方式 GB/T 7714	Shipps C.,Ray Kelly H.,Dahl P.J.,et al. Intrinsic electronic conductivity of individual atomically resolved amyloid crystals reveals micrometer-long hole hopping via tyrosines[J],2021,118(2).
APA	Shipps C..,Ray Kelly H..,Dahl P.J..,Yi S.M..,Vu D..,...&Malvankar N.S..(2021).Intrinsic electronic conductivity of individual atomically resolved amyloid crystals reveals micrometer-long hole hopping via tyrosines.Proceedings of the National Academy of Sciences of the United States of America,118(2).
MLA	Shipps C.,et al."Intrinsic electronic conductivity of individual atomically resolved amyloid crystals reveals micrometer-long hole hopping via tyrosines".Proceedings of the National Academy of Sciences of the United States of America 118.2(2021).