NewScientist.com: A hydrogen fuel cell that uses enzymes instead of expensive metal catalysts to drive chemical reactions has been developed by UK researchers.

… Researchers from Oxford University in the UK used two enzymes, one harvested from bacteria and the other from fungus, to catalyse the same chemical reactions. Each electrode is coated in one of the two enzymes. The bacterial enzymes break down hydrogen as part of their natural metabolism, and the fungal enzymes naturally combine hydrogen with oxygen – usually to break down wood.

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