Steve Connor: Spreading a little sunshine for the dawn of a new age

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The Independent Online

It is fair to say that without photosynthesis life on Earth would be very different. It is arguably the most critical biological process. It has allowed life to flourish but it is also the basis of advanced, industrialised societies which are built on the energy of fossil fuels stored in the ground. Plants have developed a form of energy conversion that scientists would love to emulate. Using a pigment, chlorophyll, and a sophisticated bagfull of enzymes called a chloroplast, plants are able to convert the energy of the sun, and the carbon dioxide of the air, into a chemical fuel that can be stored as a fossil fuel for millions of years.

All fossil fuels are effectively stores of underground sunshine, courtesy of photosynthesis. When we burn oil, coal or gas we are in effect reversing the process of photosynthesis – we are converting plant hydrocarbons into carbon dioxide and energy.

Much of the emphasis on re-creating photosynthesis as an alternative energy source has concentrated on manipulating natural photosynthesisers, such as algae. What the latest study at the Massachusetts Institute of Technology has done is to try to create a totally synthetic system based on a genetically modified virus that normally infects bacteria, combined with a pigment to trap sunlight and a catalyst to speed up the photosynthetic chemical reactions.

It is still early days, but the scientists have made a breakthough in the first stage of the photosynthetic process, the collection of oxygen from water. The next stage would be to create hydrogen, a useful, carbon-free fuel that can be burnt in air to produce nothing more noxious than water.

The scientists overcame several problems, such as the tendency of the viral "wires" to clump together by encapsulating them in a microgel matrix. But they will have to come up with many other technical fixes before the system can become an artificial photosynthesis factory.

Nevertheless, this is an exciting first step that could one day lead to the reality of "synthetic life forms" trapping sunlight for the benefit of humankind. It could be one solution to our energy and environmental crises.