Scientists have been trying for a while now to recreate the process of photosynthesis, using sunlight and water to spark chemical reactions. Now a team from Penn State University has done one better, producing an engineered biological system that can produce a hydrogen biofuel twice as fast as nature.
The system uses a molecular wire to facilitate fast movement of electrons between light-capturing enzymes, which are used to split water into molecular oxygen and hydrogen. It could someday serve as a fast and reliable way to derive hydrogen for use in fuel cells.Researchers led by Carolyn Lubner at Penn State worked with a cyanobacterium called Synechococcus and another bacterium, Clostridium acetobutylicum. In nature, photosynthetic organisms use light-capturing enzymes nicknamed Photosystem I and II, which absorb light and excite electrons to a higher energy state. Another enzyme called FNR then uses these electrons to produce an energy-storage molecule. This molecule is used to make sugars to keep the organism alive, and that's your basic photosynthesis process.