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arXiv · 1502.00544

3D-localization microscopy and tracking of FoF1-ATP synthases in living bacteria

Anja Renz·Marc Renz·Diana Kluetsch·Gabriele Deckers-Hebestreit·Michael Börsch
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Abstract

FoF1-ATP synthases are membrane-embedded protein machines that catalyze the synthesis of adenosine triphosphate. Using photoactivation-based localization microscopy (PALM) in TIR-illumination as well as structured illumination microscopy (SIM), we explore the spatial distribution and track single FoF1-ATP synthases in living E. coli cells under physiological conditions at different temperatures. For quantitative diffusion analysis by mean-squared-displacement measurements, the limited size of the observation area in the membrane with its significant membrane curvature has to be considered. Therefore, we applied a 'sliding observation window' approach (M. Renz et al., Proc. SPIE 8225, 2012) and obtained the one-dimensional diffusion coefficient of FoF1-ATP synthase diffusing on the long axis in living E. coli cells.

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Anja Renz, Marc Renz, Diana Kluetsch, Gabriele Deckers-Hebestreit, Michael Börsch. 2015-02-02. 3D-localization microscopy and tracking of FoF1-ATP synthases in living bacteria. https://doi.org/10.1117/12.2080981

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