Monitoring of rotational movements in nanomotors by single molecule fluorescence resonance energy transfer

• Applicant: Dr. Eva Maria Gálvez Buerba
• Subject Area: Biological and Biomimetic Chemistry
• Term: from 2006 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 19043592

Several functions of living beings take place through proteic complex that act as molecular nanomotors. Inside these nanomotors there are some complexes to develop rotational movements as the movement of ATP synthase (ATPase) during the ATP synthesis. ATPase is the main energy producer in living beings in form of ATP. ATP synthases are enzymes that produce ATP from ADP and phosphate by using the energy derived from an electrochemical proton gradient. ATPases consist of two parts, F1 and F0. ATP synthesis takes place at the β-subunits of F1, which run through a sequence of different conformations during catalysis. Rotation of the γ-subunit is assumed to be coupled mechanically to proton translocation by a rotational movement of the c-ring in the F0-part. Therefore, the subunits are also defined as rotor (γεcn) and stator (α3β3γab2). The mechanism of this enzyme has been extensively studied, although the details of energy transduction are not fully understood and need further research mainly due to technical limitations of the systems used. The aim of this work is to clarify the molecular events that control this rotational mechanism in order to get more knowledge about the mechanism of this enzyme. For that we have planed to use quantum dots to establish a new FRET (Fluorescence Resonance Energy Transfer) system with a high photostability, which will allow us to analyse in detail, the mechanism of action of H+-ATP synthases, including different sub-steps of the rotary mechanism of this enzyme.

• DFG Programme: Research Fellowships
• Host: Professor Dr.-Ing. Peter Gräber