Resonance energy transfer improves the biological function of bacteriorhodopsin within a hybrid material built from purple membranes and semiconductor quantum dots.
Fiche publication
Date publication
juillet 2010
Journal
Nano letters
Auteurs
Membres identifiés du Cancéropôle Est :
Pr NABIEV Igor
Tous les auteurs :
Rakovich A, Sukhanova A, Bouchonville N, Lukashev E, Oleinikov V, Artemyev M, Lesnyak V, Gaponik N, Molinari M, Troyon M, Rakovich YP, Donegan JF, Nabiev I
Lien Pubmed
Résumé
Purple membrane (PM) from bacteria Halobacterium salinarum contains a photochromic protein bacteriorhodopsin (bR) arranged in a 2D hexagonal nanocrystalline lattice (Figure 1 ). Absorption of light by the protein-bound chromophore retinal results in pumping the protons through the PM creating an electrochemical gradient which is then used by the ATPases to energize the cellular processes. Energy conversion, photochromism, and photoelectrism are the inherent effects which are employed in many bR technical applications. bR, along with the other photosensitive proteins, is not able to deal with the excess energy of photons in UV and blue spectral region and utilizes less than 0.5% of the energy from the available incident solar light for its biological function. Here, we proceed with optimization of bR functions through the engineering of a "nanoconverter" of solar energy based on semiconductor quantum dots (QDs) tagged with the PM. These nanoconverters are able to harvest light from deep-UV to the visible region and to transfer this additionally collected energy to bR via Förster resonance energy transfer (FRET). We show that specific nanobio-optical and spatial coupling of QDs (donor) and bR retinal (acceptor) provide a means to achieve FRET with efficiency approaching 100%. We have finally demonstrated that the integration of QDs within PM significantly increases the efficiency of light-driven transmembrane proton pumping, which is the main bR biological function. This new QD-PM hybrid material will have numerous optoelectronic, photonic, and photovoltaic applications based on its energy conversion, photochromism, and photoelectrism properties.
Mots clés
Archaeal Proteins, chemistry, Bacteriorhodopsins, chemistry, Fluorescence Resonance Energy Transfer, methods, Halobacterium salinarum, chemistry, Purple Membrane, chemistry, Quantum Dots, Semiconductors
Référence
Nano Lett.. 2010 Jul;10(7):2640-8