Gating of single synthetic nanopores by proton-driven DNA molecular motors.
Switchable ion channels that are made of membrane proteins play different roles in cellular circuits. Since gating nanopore channels made of proteins can only work in the environment of lipid membrane, they are not fully compatible to the application requirement as a component of those nanodevice systems in which lipid membranes are hard to establish. Here we report a synthetic nanopore-DNA system where single solid-state conical nanopores can be reversibly gated by switching DNA motors immobilized inside the nanopores. High- (on-state) and low- (off-state) conductance states were found within this nanopore-DNA system corresponding to the single-stranded and i-motif structures of the attached DNA motors. The highest gating efficiency indicated as current ratio of on-state versus off-state was found when the length of the attached DNA molecule matched the tip diameter of the nanopore well. This novel nanopore-DNA system, which was gated by collective folding of structured DNA molecules responding to the external stimulus, provided an artificial counterpart of switchable protein-made nanopore channels. The concept of this DNA motor-driven nanopore switch can be used to build novel, biologically inspired nanopore machines with more precisely controlled functions in the near future by replacing the DNA molecules with other functional biomolecules, such as polypeptides or protein enzymes.
Xia
Fan
F
Center of Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
Guo
Wei
W
Mao
Youdong
Y
Hou
Xu
X
Xue
Jianming
J
Xia
Hongwei
H
Wang
Lin
L
Song
Yanling
Y
Ji
Hang
H
Ouyang
Qi
Q
Wang
Yugang
Y
Jiang
Lei
L
D004247:DNA / Q000737:chemistry*; D007473:Ion Channels / Q000737:chemistry*; D018716:Molecular Mimicry; D009690:Nucleic Acid Conformation; D016062:Porosity; D011522:Protons
D007473:Ion Channels; D011522:Protons; D004247:DNA