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Scientists have successfully replicated one of the crucial steps in photosynthesis, paving the way for a new breed of solar energy.

The process recreated in the lab could lead to the development of an efficient supply of hydrogen-based fuel.

Hydrogen offers potential as a carbon-neutral replacement for petrol, but until now, the way in which plants produced hydrogen by splitting water molecules was poorly understood.

Dr Kastoori Hingorani (pictured, left, ) and Professor Ron Pace (pictured, right, with the protein in a container) hope the research will open up possibilities for manufacturing hydrogen as a cheap and clean source of fuel

'Water is abundant and so is sunlight. It is an exciting prospect to use them to create hydrogen, and do it cheaply and safely,' said Dr Kastoori Hingorani, from the Australian Research Council's Centre of Excellence for Translational Photosynthesis at the Australian National Universit.

The team created a protein that, when exposed to light, displayed the electrical 'heartbeat' key to photosynthesis.

The naturally-occurring protein does not require batteries or expensive metals, suggesting the process could one day provide an affordable energy source in developing countries, Dr Hingorani added.

Co-researcher Professor Ron Pace said the research opened up new possibilities for manufacturing hydrogen as a cheap and clean source of fuel.

'This is the first time we have replicated the primary capture of energy from sunlight,' Professor Pace said.

'It's the beginning of a whole suite of possibilities, such as creating a highly efficient fuel, or to trapping atmospheric carbon.'

Professor Pace said large amounts of hydrogen fuel produced by artificial photosynthesis could transform the economy.

Last month it was reported that a functioning man-made leaf (pictured) that absorbs water and carbon dioxide to produce oxygen, just like natural leaves, was been created by an art graduate

'That 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,' he said.

The team modified a protein called ferritin, which is present in almost all living organisms.

Ferritin's usual role is to store iron, but the team removed the iron and replaced it with the abundant metal, manganese, to closely resemble the water splitting site in photosynthesis.

Scientists also added a light-sensitive pigment, zinc chlorin, to the protein.

When researchers shone light onto the modified ferritin, there was a clear indication of charge transfer just like that seen in natural photosynthesis.

The study was inspired by Associate Professor Warwick Hillier, who led the research group until his death from brain cancer, earlier this year.

'Associate Professor Hillier imagined modifying E. coli so that it expresses the gene to create ready-made artificial photosynthetic proteins. 

'It would be a self-replicating system – all you need to do is shine light on it,' Dr Hingorani said.