Conformational change of bacteriorhodopsin quantitatively monitored by microcantilever sensors.
Bacteriorhodopsin proteoliposomes were used as a model system to explore the applicability of micromechanical cantilever arrays to detect conformational changes in membrane protein patches. The three main results of our study concern: 1), reliable functionalization of micromechanical cantilever arrays with proteoliposomes using ink jet spotting; 2), successful detection of the prosthetic retinal removal (bleaching) from the bacteriorhodopsin protein by measuring the induced nanomechanical surface stress change; and 3), the quantitative response thereof, which depends linearly on the amount of removed retinal. Our results show this technique to be a potential tool to measure membrane protein-based receptor-ligand interactions and conformational changes.
Braun
Thomas
T
National Center of Competence for Research in Nanoscale Science, Institute of Physics, and Maurice E. Müller Institute, Biozentrum, University of Basel, 4056 Basel, Switzerland.
Backmann
Natalija
N
Vögtli
Manuel
M
Bietsch
Alexander
A
Engel
Andreas
A
Lang
Hans-Peter
HP
Gerber
Christoph
C
Hegner
Martin
M
D001436:Bacteriorhodopsins / Q000737:chemistry*; D001696:Biomechanical Phenomena; D015374:Biosensing Techniques; D018625:Microscopy, Atomic Force; D036103:Nanotechnology; D038761:Photobleaching; D040081:Protein Array Analysis; D011487:Protein Conformation; D011510:Proteolipids / Q000737:chemistry; D012172:Retinaldehyde / Q000737:chemistry
D011510:Proteolipids; C020485:proteoliposomes; D001436:Bacteriorhodopsins; D012172:Retinaldehyde