Biophysical Society Thematic Meeting| Lima 2019

Revisiting the Central Dogma of Molecular Biology at the Single-Molecule Level

Poster Abstracts

34-POS Board 34 EXPLORING THE ROTATION OF THE GAMMA SHAFT OF F1-ATPASE IN SINGLE-MOLECULE EXPERIMENTS Ricardo A Matute 1,2 ; Sándor Volkán-Kacsó 1 ; Rudolph A Marcus 1 ; 1 California Institute of Technology, Division of Chemistry and Chemical Engineering, Pasadena, CA, USA 2 Universidad Bernardo O'Higgins, Centro Integrativo de Biología y Química Aplicada (CIBQA), Santiago, Chile Single-molecule imaging experiments provide information that is not available from ensemble experiments. We are interested in the interpretation of dynamical studies imaging and manipulation in F1-ATPase single-molecules. One key question that has arisen in single molecule stalling experiments is the erratic behavior a rotor angle of 55° between the binding and hydrolysis dwell angles of 0 and 80°, respectively. In our previous theoretical work, we used the elastic property of the rotor-stator structure to treat the experiments on controlled rotation. Our modelling suggests that there has to be a change in the bonding network, for example, of hydrogen bonds, as the system transitions between the two dwell points, perhaps at 55°, as indicated by an unusual stalling behavior around that angle. In the present work, we performed full-atomistic molecular dynamics (MD) simulations on the F1-ATPase to explore the rotation of the gamma shaft of F1-ATPase, thus capturing the main conformational changes from an “open” to a “closed” conformation of the catalytic beta subunits, which are associated to the rotation of the gamma shaft of F1-ATPase in single-molecule experiments. Acknowledgements R.A.M. acknowledges the FONDECYT Grant No. 1181260. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562.

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