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Scientists have for the first time in detail, able to follow what happens when green plants convert sunlight and water into energy, oxygen and hydrogen.

With the help of new technology with very short pulses of x-ray laser, scientists have been snapshots of what is happening at the molecular level during the first part of photosynthesis: when a protein uses sunlight to split the water molecules.

- Previously, we have only been able to watch the static system where there is no movement. But because it is so short pulses, we can now see what it is the protein that changes when water is broken down, said Carl Caleman, researchers at the Department of Physics and Astronomy at Uppsala University.

The pulses are really very short - one thousandth of a trillion of a second - and contains so many photons that the effect is greater than if all the sunlight that hits the earth could be collected and focused to a square millimeter. Carl Caleman compare it to a camera with a very fast shutter speed.

- A camera can not capture motion that occurs while the shutter is open. But with these short pulses, we can look at things that are happening quickly and access dynamics.

Carl Caleman part of a research by including German, American and Swedish physicists and biologists who made the experiments using X-ray laser LCLS at SLAC National Accelerator Laboratory in California.

The protein they are studying is called photosystem second researchers created crystals of the protein, called on it with light similar to sunlight, and then pelted it with X-ray laser pulses. When a pulse is passed through a crystal is picked up on a screen, forming a pattern that tells how the protein looks like in that particular moment.

The researchers had different lengths of time to go between sunlight and x-ray laser pulse, and was thus almost a movie that shows how the protein changes during the process. The results are published in this week's issue of the journal Nature.

Photosynthesis, in which green plants and algae convert carbon dioxide, water and sunlight into food and oxygen, is the key to life as we know it on Earth. If we better understand how it works, in the future we create artificial photosynthesis and better solar panels.

Biologists of the research team were surprised that the whole of the large protein complex was affected in the process and not just the active core. But Carl Caleman think it is the technology that is the big breakthrough.

- I am a physicist, and I'm most excited that we were able to show that this technique works. Now we can use it to watch other chemical processes, how the structure of different proteins in our body change as a result of such a change in the pH value, he says.