The report by a team of researchers at Wake Forest University School of Medicine, published in the journal Nature, said large amounts of hydrogen peroxide are produced when the immune system is activated in response to bacteria.

The team used X-ray crystallography to create a three-dimensional snapshot of how the proteins interact.

Scientists said a molecule known as peroxiredoxin (Prx) helps control levels of hydrogen peroxide. If levels of hydrogen peroxide become too high, the cell's DNA and other proteins can be damaged.

"It basically acts as a sensor and warns the cell that levels are too high and that the cell needs to respond," lead author Thomas J. Jonsson said in a news release. "Once that threat is gone, Prx needs to go back to its normal state."

Prx becomes active again by binding with a protein known as sulfiredoxin, the report said.

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