liposome; reconstitution; ATP synthase; SNARE protein; membrane protein; respiratory chain; giant unilamellar vesicle; membrane fusion
Belevich Nikolai, von Ballmoos Christoph, Verkhovskaya Marina (2017), Activation of Proton Translocation by Respiratory Complex I., in Biochemistry
, 56(42), 5691-5697.
Sjöholm Johannes, Bergstrand Jan, Nilsson Tobias, Šachl Radek, Ballmoos Christoph von, Widengren Jerker, Brzezinski Peter (2017), The lateral distance between a proton pump and ATP synthase determines the ATP-synthesis rate., in Scientific reports
, 7(1), 2926-2926.
Biner Olivier, Schick Thomas, Müller Yannic, von Ballmoos Christoph (2016), Delivery of membrane proteins into small and giant unilamellar vesicles by charge-mediated fusion., in FEBS letters
, 590(14), 2051-2062.
Smirnova Irina A, Sjöstrand Dan, Li Fei, Björck Markus, Schäfer Jacob, Östbye Henrik, Högbom Martin, von Ballmoos Christoph, Lander Gabriel C, Ädelroth Pia, Brzezinski Peter (2016), Isolation of yeast complex IV in native lipid nanodiscs., in Biochimica et biophysica acta
, 1858(12), 2984-2992.
Nilsson Tobias, Lundin Camilla Rydström, Nordlund Gustav, Ädelroth Pia, von Ballmoos Christoph, Brzezinski Peter (2016), Lipid-mediated Protein-protein Interactions Modulate Respiration-driven ATP Synthesis., in Scientific reports
, 6, 24113-24113.
von Ballmoos Christoph, Biner Olivier, Nilsson Tobias, Brzezinski Peter (2016), Mimicking respiratory phosphorylation using purified enzymes., in Biochimica et biophysica acta
, 1857(4), 321-31.
Nordlund Gustav, Brzezinski Peter, von Ballmoos Christoph (2014), SNARE-fusion mediated insertion of membrane proteins into native and artificial membranes., in Nature communications
, 5, 4303-4303.
Goals:To establish new technologies that allow the functional investigation of membrane proteins on a molecular level. A special emphasis is given on the interplay of more than one membrane protein. Methods are developed to investigate the membrane proteins in their native environment, a lipid bilayer. The developed methods are tested with membrane proteins from bacterial respiratory chains.Specific goals:•The controlled incorporation of more than one membrane protein by a “building block” strategy. Every membrane protein is first optimally reconstituted in a small liposome before they are fused into a single membrane, mediated by SNARE proteins. •Reconstituted in giant unilamellar vesicles, membranes proteins at work are directly observed under a microscope, using fluorescent techniques.•Reconstruction of an “artificial energy cell” from purified components.Scientific impact an relevance:In all life forms, biological membranes separate the contents of different compartments. Thereby, transport of molecules and communication between these compartments and thus across membranes is crucial. This task is performed by membrane proteins, the doors and windows of biological membranes. Due to their important role, MPs are the targets of more than 50% of modern drugs, making their molecular mechanism interesting for both basic and applied research. The complexity of an intact membrane, however, complicates the interpretation of many experiments, including drug binding studies to membrane bound receptors.In vitro experiments with purified components are thus necessary to elucidate the molecular details of cellular processes. The technologies outlined in this proposal are not specific for the respiratory enzymes investigated here. Instead, they are generally applicable to all kind of membrane proteins and their interaction partners. Experimental methods:Mainly spectroscopic techniques will be used to follow enzyme activities in situ. For ion translocation processes, specific fluorescent dyes will be used and the changes analyzed according to their time scale (stopped flow or normal mixing). For visualization of giant vesicles, phase contrast and fluorescent (confocal) microscopy will be used.