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

@article{Mitome2017IdentificationOA,
  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},
  year={2017},
  volume={14},
  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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4 Citations

4 Citations

Characterizing the Hydration Properties of Proton Binding Sites in the ATP Synthase C-Rings of Bacillus Species.

The data suggest that a water molecule stably binds to the P51A mutant of BacillusPS3, as well as helping to identify a bound water molecule in Bacillus PS3 whose presence was previously overlooked due to the limited resolution of the structural data.

Insights into water accessible pathways and the inactivation mechanism of proton translocation by the membrane-embedded domain of V-type ATPases.

Cooperation among c-subunits of FoF1-ATP synthase in rotation-coupled proton translocation

Simulations revealed that prolonged proton uptake in mutated c-subunits is shared between two c- subunits, explaining the cooperation observed in biochemical assays.

ATP synthase in rotation- coupled proton translocation

In FoF1ATP synthase, proton translocation through Fo drives rotation of the csubunit oligomeric ring relative to the asubunit. Recent studies suggest that in each step of the rotation, key glutamic…

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