title: Investigation of Ion Channel Activities of Gramicidin A in the Presence of Ionic Liquids Using Model Cell Membranes.
abstract: Ionic liquids (ILs) are considered to be green solvents because of their non-volatility. Although ILs are relatively safe in the atmospheric environment, they may be toxic in other environments. Our previous research showed that the cytotoxicity of ILs to biological organisms is attributable to interference with cell membranes by IL insertion. However, the effects of ILs on ion channels, which play important roles in cell homeostasis, have not been comprehensively studied to date. In this work, we studied the interactions between ILs and lipid bilayer membranes with gramicidin A ion channels. We used two methods, namely electrical and fluorescence measurements of ions that permeate the membrane. The lifetimes of channels were increased by all the ILs tested in this work via stabilizing the compressed structure of the lipid bilayer and the rate of ion flux through gA channels was decreased by changing the membrane surface charge. The former effect, which increased the rate of ion flux, was dominant at high salt concentrations, whereas the latter, which decreased the rate of ion flux, was dominant at low salt concentrations. The effects of ILs increased with increasing concentration and alkyl chain length. The experimental results were further studied using molecular dynamics simulations.
authors.affiliation: 1] Department of Biological Engineering, Inha University, Incheon 402-751, South Korea [2] Biohybrid Systems Research Center (BSRC), Inha University, Incheon 402-751, South Korea.
authors.forename: Hyunil
authors.initials: H
authors.lastname: Ryu
authors.affiliation: Department of Chemical Engineering, Dankook University, Yongin-si, Gyeonggi-do 448-701, South Korea.
authors.forename: Hwankyu
authors.initials: H
authors.lastname: Lee
authors.affiliation: Division of Bioinformatics, Graduate School of Engineering, Soka University, Tokyo 192-8577, Japan.
authors.forename: Seigo
authors.initials: S
authors.lastname: Iwata
authors.affiliation: 1] Department of Biological Engineering, Inha University, Incheon 402-751, South Korea [2] Biohybrid Systems Research Center (BSRC), Inha University, Incheon 402-751, South Korea.
authors.forename: Sangbaek
authors.initials: S
authors.lastname: Choi
authors.affiliation: School of Mechanical Engineering and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon, 440-746, Korea.
authors.forename: Moon Ki
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Institute of Life Sciences and Resources, and Department of Food Science and Biotechnology, Kyung Hee University, Yongin 446-701, South Korea.
authors.forename: Young-Rok
authors.initials: YR
authors.lastname: Kim
authors.affiliation: Division of Bioinformatics, Graduate School of Engineering, Soka University, Tokyo 192-8577, Japan.
authors.forename: Shinsaku
authors.initials: S
authors.lastname: Maruta
authors.affiliation: 1] Biohybrid Systems Research Center (BSRC), Inha University, Incheon 402-751, South Korea [2] Department of Mechanical Engineering, Inha University, Incheon 402-751, South Korea.
authors.forename: Sun Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: 1] Department of Biological Engineering, Inha University, Incheon 402-751, South Korea [2] Biohybrid Systems Research Center (BSRC), Inha University, Incheon 402-751, South Korea.
authors.forename: Tae-Joon
authors.initials: TJ
authors.lastname: Jeon
mesh_terms: D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D006096:Gramicidin / Q000737:chemistry* / Q000378:metabolism; D007473:Ion Channels / Q000737:chemistry / Q000378:metabolism; D052578:Ionic Liquids / Q000737:chemistry*; D007477:Ions / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008081:Liposomes; D056004:Molecular Dynamics Simulation
chemical_list: D007473:Ion Channels; D052578:Ionic Liquids; D007477:Ions; D008051:Lipid Bilayers; D008081:Liposomes; D006096:Gramicidin