Effect of protein orientation on electron transfer between photosynthetic reaction centers and carbon electrodes

RETRACTED: Monolayers of pigment-protein complexes on a bare gold electrode: Orientation controlled deposition and comparison of electron transfer rate for two configurations

“…2B). The observation of cathodic current in similar experiments is attributed to transfer of electrons from working electrode to special pair of RC complex (den Hollander et al, 2011;Lebedev et al, 2006;Swainsbury et al, 2014;Trammell et al, 2006). By using only 100 mM Q-0 as a mediator, a photocurrent of 1100 7 8 nA/cm 2 for forward-dipped and 1057 5 nA/cm 2 for reverse-dipped film was recorded.…”

“…The electron transfer in RC is unidirectional that is from primary donor to terminal acceptor. The observation of cathodic current indicates that the electron transfer is taking place from electrode to RC, which is contributed by only those RCs having their primary donor side facing the electrode (den Hollander et al, 2011;Trammell et al, 2006). The large difference in magnitude of photocurrent for forward-and reverse-dipped LB films show that the majority of RC-LH1 complexes for forward-dipped films are attached to the electrode with their primary donor side facing the electrode, whereas for reverse-dipped films, only a small fraction of molecules have this particular orientation.…”

Superhydrophobic Carbon Nanotube Electrode Produces a Near‐Symmetrical Alternating Current from Photosynthetic Protein‐Based Photoelectrochemical Cells

“…It is worth noting that two of the major challenges in the development of nanoscale molecular logic gates are the integration of such devices with conventional electronic components, and the transition from ensembles to individual molecules. It is now well established that photoreaction centres can be interfaced with conducting metal surfaces in a productive manner, [17][18][19][20][21][22][23][24][25] and these proteins are also at the forefront of research on nanoscale patterning of molecules on surfaces (e.g. see ref.…”

“…Photoelectrochemical cells based on electrodes coated with a variety of photosynthetic proteins have been observed to produce a similar light-dependent DC output. [17][18][19][20][21][22][23][24][25] However, novel protein-based photoelectrochemical cells have recently been described that produce a conventional DC in response to continuous illumination, but an unusual alternating current (AC) under conditions of discontinuous illumination. [ 26 ] These cells use as the photovoltaic material either the reaction center pigment-protein from the purple bacterium Rhodobacter ( Rba. )…”

Photoelectron Generation by Photosystem II Core Complexes Tethered to Gold Surfaces

“…Although progress in the fields of genomics, molecular genetics, biochemistry, biophysics, materials science, and engineering makes such devices tantalizingly close, a functional device has remained elusive. Membranes with oriented photosynthetic RCs have been assembled, [5][6][7] and attempts have been made to integrate photosynthetic protein complexes into solid-state devices, such as photodetectors and photovoltaic cells. [8] PSII core complexes have been immobilized onto electrodes for assembling biosenBy using a nondestructive, ultrasensitive, fluorescence kinetic technique, we measure in situ the photochemical energy conversion efficiency and electron transfer kinetics on the acceptor side of histidine-tagged photosystem II core complexes tethered to gold surfaces.…”