Photosynthetic Hydrogen Production by a Hybrid Complex of Photosystem I and [NiFe]-Hydrogenase

Abstract

Nature provides key components for generating fuels from renewable resources in the form of enzymatic nanomachines which catalyze crucial steps in biological energy conversion, for example, the photosynthetic apparatus, which transforms solar power into chemical energy, and hydrogenases, capable of generating molecular hydrogen. As sunlight is usually used to synthesize carbohydrates, direct generation of hydrogen from light represents an exception in nature. On the molecular level, the crucial step for conversion of solar energy into H(2) lies in the efficient electronic coupling of photosystem I and hydrogenase. Here we show the stepwise assembly of a hybrid complex consisting of photosystem I and hydrogenase on a solid gold surface. This device gave rise to light-induced H(2) evolution. Hydrogen production is possible at far higher potential and thus lower energy compared to those of previously described (bio)nanoelectronic devices that did not employ the photosynthesis apparatus. The successful demonstration of efficient solar-to-hydrogen conversion may serve as a blueprint for the establishment of this system in a living organism with the paramount advantage of self-replication.

Interactions of Photosystem I with Plasmonic nanostructures

“…Such patterns can be produced by nanosphere lithography [8,9]; an inexpensive, inherently parallel, high-throughput nanofabrication technique capable of producing well-ordered 2D periodic nanostructure arrays from all dierent kinds of vaporizable materials [8,9]. The size of the nanostruc- or chemical energy [10,19,20]. Among the 100 chlorophylls some chlorophyll dimers and trimers with lower site energies than the reaction center with its main absorbance at 700 nm (P700) were found [2126].…”

Photobioelectrochemistry: Solar Energy Conversion and Biofuel Production with Photosynthetic Catalysts

“…This device was able to generate H 2 at a rate of 120 pmol s −1 cm −2 or 4500 mol H 2 min −1 mol −1 PSI-hydrogenase complex. 74 A more common method of H 2 production is to use a two-phase process as seen in the device reported by McCormick et al 75 The cyanobacterium Synechocystis sp. PCC 6803 was used in the fueling phase to reduce ferricyanide while illuminated with the circuit open.…”

Novel Hydrogen Bioreactor and Detection Apparatus

“…This detector was used as an alternative to simple endpoint gas composition determination by gas chromatography, as is sometimes used in some biohydrogen studies [22,23]. Such detection methods enable accurate measurement of produced gas, but have the limitations of cost, maintenance, and requiring several minutes per sample, preventing the precise measurement of hydrogen production in systems of quickly changing hydrogen Fig.…”