Activation and Stiffness of the Inhibited States of F1-ATPase Probed by Single-molecule Manipulation

@article{Saita2010ActivationAS,
  title={Activation and Stiffness of the Inhibited States of F1-ATPase Probed by Single-molecule Manipulation},
  author={Ei-ichiro Saita and Ryota Iino and Toshiharu Suzuki and Boris A. Feniouk and Kazuhiko Kinosita and Masasuke Yoshida},
  journal={The Journal of Biological Chemistry},
  year={2010},
  volume={285},
  pages={11411 - 11417}
}
F1-ATPase (F1), a soluble portion of FoF1-ATP synthase (FoF1), is an ATP-driven motor in which γϵ subunits rotate in the α3β3 cylinder. Activity of F1 and FoF1 from Bacillus PS3 is attenuated by the ϵ subunit in an inhibitory extended form. In this study we observed ATP-dependent transition of ϵ in single F1 molecules from extended form to hairpin form by fluorescence resonance energy transfer. The results justify the previous bulk experiments and ensure that fraction of F1 with hairpin… 

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