Researchers have artificially replicated steps of photosynthesis to produce hydrogen as a zero-carbon replacement for petroleum products. A team from Australian National University modified the naturally occurring protein ferritin to display a transfer of electrical pulses when exposed to sunlight in water. Ferritin’s usual role is to store iron and is found in almost all living organisms. The researchers replaced the iron with manganese to closely resemble the water-splitting site in photosynthesis. The protein was also pigmented with light-sensitive zinc chlorin. “This is the first time we have replicated the primary capture of energy from sunlight,” said professor Dr. Ron Pace. “It’s the beginning of a whole suite of possibilities, such as creating a highly efficient fuel, or to trapping atmospheric carbon.” The late professor Warwick Hillier modified E. coli so that it expressed the gene to create ready-made artificial photosynthetic proteins. The system would be self-replicating with a light source. “A carbon-free cycle is essentially indefinitely sustainable. Sunlight is extraordinarily abundant, water is everywhere — the raw materials we need to make the fuel. And at the end of the usage cycle it goes back to water,” Pace said. The research was published in BBA Bioenergetics (doi: 10.1016/j.bbabio.2014.07.019). For more information, visit www.biology.anu.edu.au.