FASTER, PLEASE: Gut enzyme could help solve U.S. blood shortages. “An enzyme found in gut bacteria could convert type A blood into universal type O blood, a scientific feat that would significantly boost blood supplies, a new study suggests. This enzyme converts A blood into O blood approximately 30 times faster than any enzyme on record, and it appears to do it in a safe and effective manner, said lead researcher Stephen Withers, a professor of biochemistry with the University of British Columbia.”