Proton uptake mechanism in bacteriorhodopsin captured by serial synchrotron crystallography

Weinert, T.; Skopintsev, P.; James, D.; Dworkowski, F.; Panepucci, E.; Kekilli, D.; Furrer, A.; Brünle, S.; Mous, S.; Ozerov, D.; Nogly, P.; Wang, M.; Standfuss, J.

doi:10.1101/576629

bioRxiv · 10.1101/576629

Proton uptake mechanism in bacteriorhodopsin captured by serial synchrotron crystallography

Weinert, T.·Skopintsev, P.·James, D.·Dworkowski, F.·Panepucci, E.·Kekilli, D.·Furrer, A.·Brünle, S.·Mous, S.·Ozerov, D.·Nogly, P.·Wang, M.·Standfuss, J.

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Abstract

Conformational dynamics are essential for proteins to function. Here we describe how we adapted time-resolved serial crystallography developed at X-ray lasers to visualize protein motions using synchrotrons. We recorded the structural changes upon proton pumping in bacteriorhodopsin over 200 ms in time. The snapshot from the first 5 ms after photoactivation shows structural changes associated with proton release at comparable quality to previous X-ray laser experiments. From 10-15 ms onwards we observe large additional structural rearrangements up to 9 [A] on the cytoplasmic side. Rotation of Leu93 and Phe219 opens a hydrophobic barrier leading to the formation of a water chain connecting the intracellular Asp96 with the retinal Schiff base. The formation of this proton wire recharges the membrane pump with a proton for the next cycle.

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Weinert, T., Skopintsev, P., James, D., Dworkowski, F., Panepucci, E., Kekilli, D., Furrer, A., Brünle, S., Mous, S., Ozerov, D., Nogly, P., Wang, M., Standfuss, J.. 2019-03-14. Proton uptake mechanism in bacteriorhodopsin captured by serial synchrotron crystallography. https://doi.org/10.1101/576629

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