WASHINGTON - Researchers say they have taken another step toward understanding how plants split water into hydrogen and oxygen atoms — which may provide a cheap way to produce clean-burning hydrogen fuel. advertisement

Producing hydrogen from water is the stuff of science fiction — and some comments by President Bush. But the team at Imperial College London and Japan Science and Technology Corp. in Yokohama said they had taken the best pictures yet of the plant structures that do it every day.

They used high-resolution X-ray crystallography to make an image of the tiny atomic splitter that separates the two hydrogen atoms from an oxygen atom in a water molecule.

“Results by other groups, including those obtained using lower-resolution X-ray crystallography at 3.7 angstroms, have shown that the splitting of water occurs at a catalytic center that consists of four manganese atoms,” said So Iwata of Imperial’s Department of Biological Sciences.

“We’ve taken this further by showing that three of the manganese atoms, a calcium atom and four oxygen atoms, form a cubelike structure, which brings stability to the catalytic center,” Iwata added in a statement. “Together this arrangement gives strong hints about the water-splitting chemistry.”

Bacterium studied

atoms, form a cubelike structure, which brings stability to the catalytic center,” Iwata added in a statement. “Together this arrangement gives strong hints about the water-splitting chemistry.”

atoms, form a cubelike structure, which brings stability to the catalytic center,” Iwata added in a statement. “Together this arrangement gives strong hints about the water-splitting chemistry.”