2022年10月14日
Ion transfer mechanisms in Mrp-type antiporters from high resolution cryoEM and molecular dynamics simulations
Nature Communications
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- 巻
- 13
- 号
- 1
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1038/s41467-022-33640-y
- 出版者・発行元
- Springer Science and Business Media {LLC}
<jats:title>Abstract</jats:title><jats:p>Multiple resistance and pH adaptation (Mrp) cation/proton antiporters are essential for growth of a variety of halophilic and alkaliphilic bacteria under stress conditions. Mrp-type antiporters are closely related to the membrane domain of respiratory complex I. We determined the structure of the Mrp antiporter from <jats:italic>Bacillus pseudofirmus</jats:italic> by electron cryo-microscopy at 2.2 Å resolution. The structure resolves more than 99% of the sidechains of the seven membrane subunits MrpA to MrpG plus 360 water molecules, including ~70 in putative ion translocation pathways. Molecular dynamics simulations based on the high-resolution structure revealed details of the antiport mechanism. We find that switching the position of a histidine residue between three hydrated pathways in the MrpA subunit is critical for proton transfer that drives gated trans-membrane sodium translocation. Several lines of evidence indicate that the same histidine-switch mechanism operates in respiratory complex I.</jats:p>
- ID情報
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- DOI : 10.1038/s41467-022-33640-y
- ISSN : 2041-1723
- ORCIDのPut Code : 131505699