Identification of aqueous access residues of the sodium half channel in transmembrane helix 5 of the Fo-a subunit of Propionigenium modestum ATP synthase

  title={Identification of aqueous access residues of the sodium half channel in transmembrane helix 5 of the Fo-a subunit of Propionigenium modestum ATP synthase},
  author={Noriyo Mitome and Hiroki Sato and Taishi Tomiyama and Katsuya Shimabukuro and Takuya Matsunishi and Kohei Hamada and Toshiharu Suzuki},
  journal={Biophysics and Physicobiology},
  pages={41 - 47}
The Fo-a subunit of the Na+-transporting FoF1 ATP synthase from Propionigenium modestum plays a key role in Na+ transport. It forms half channels that allow Na+ to enter and leave the buried carboxyl group on Fo-c subunits. The essential Arg residue R226, which faces the carboxyl group of Fo-c subunits in the middle of transmembrane helix 5 of the Fo-a subunit, separates the cytoplasmic side and periplasmic half-channels. To elucidate contributions of other amino acid residues of transmembrane… 
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