Like lifelong Floridians dropped into a Wisconsin winter, enzymes accustomed to warmth don’t always fare well in colder climes. But ancient heat-loving enzymes forced to adapt to a cooling Earth managed to swap out parts to keep chemical reactions going, scientists report online December 22 in Science.
By reconstructing enzymes as they might have looked billions of years ago, the research “helps to explain the natural evolutionary history of life on this planet,” says Yousif Shamoo, a biochemist at Rice University in Houston who wasn’t part of the study. And the findings question the idea that enzymes must sacrifice their stability to become more active.