Regulatory conformational changes of the Ɛ subunit in single FRET-labeled F0F1-ATP synthase

@inproceedings{Duncan2014RegulatoryCC,
  title={Regulatory conformational changes of the Ɛ subunit in single FRET-labeled F0F1-ATP synthase},
  author={Thomas M. Duncan and Monika G. D{\"u}ser and Thomas Heitkamp and Duncan G. G. McMillan and Michael B{\"o}rsch},
  booktitle={Photonics West - Biomedical Optics},
  year={2014}
}
Subunit ε is an intrinsic regulator of the bacterial FoF1-ATP synthase, the ubiquitous membrane-embedded enzyme that utilizes a proton motive force in most organisms to synthesize adenosine triphosphate (ATP). The C-terminal domain of ε can extend into the central cavity formed by the α and β subunits, as revealed by the recent X-ray structure of the F1 portion of the Escherichia coli enzyme. This insertion blocks the rotation of the central γ subunit and, thereby, prevents wasteful ATP… 
The regulatory subunit ε in Escherichia coli FOF1-ATP synthase.
Observing single FoF1-ATP synthase at work using an improved fluorescent protein mNeonGreen as FRET donor
TLDR
The novel FRET donor mNeonGreen is evaluated as a fusion to FoF1-ATP synthase and compare it to the previously used fluorophore EGFP to evaluate the biochemical purification procedures and activity measurements of the fully functional mutant enzyme.
Conformational dynamics of the rotary subunit F in the A3B3DF complex of Methanosarcina mazei Gö1 A‐ATP synthase monitored by single‐molecule FRET
TLDR
This work investigated the nucleotide‐dependent conformational changes of subunit F relative to subunit D during ATP hydrolysis in the A3B3DF complex of the Methanosarcina mazei Gö1 A‐ATP synthase using single‐molecule Förster resonance energy transfer and found two conformations.
Fast ATP-Dependent Subunit Rotation in Reconstituted FoF1-ATP Synthase Trapped in Solution.
TLDR
It is reported that kinetic monitoring of functional rotation can be prolonged from milliseconds to seconds by utilizing an anti-Brownian electrokinetic trap (ABEL trap), and broad distributions of ATP-dependent catalytic rates were revealed.
Insights into the regulatory function of the ɛ subunit from bacterial F-type ATP synthases: a comparison of structural, biochemical and biophysical data
TLDR
It is concluded that the ɛ subunit from the bacterial F-type ATP synthases is indeed capable of regulating ATP hydrolysis activity in a wide variety of bacteria, making it a potentially valuable drug target, but its exact role is still under debate.
The NMR solution structure of Mycobacterium tuberculosis F‐ATP synthase subunit ε provides new insight into energy coupling inside the rotary engine
TLDR
The Mtε structure provides a novel mechanistic model of coupling c‐ring‐ and ε rotation via a patch of hydrophobic residues in the NTD and residues of the CTD to the bottom of the catalytic α3β3‐headpiece.
Three‐color confocal Förster (or fluorescence) resonance energy transfer microscopy: Quantitative analysis of protein interactions in the nucleation of actin filaments in live cells
TLDR
3‐color FRET assays further support in vitro results about the role of IQGAP1, Rac1, and CDC42 in actin nucleation, and the differential impact of Rac1 and Cdc42 on the association of N‐WASP with IQG AP1.

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TLDR
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