Researchers from the Mayo Clinic in Florida found the enzyme known as BACE2 destroys beta-amyloid, a toxic protein fragment in the brains of patients who have Alzheimer's disease.
The study led by Malcolm A Leissring tested hundreds of enzymes for the ability to lower beta-amyloid levels.
BACE2 was found to lower beta-amyloid more effectively than all other enzymes tested.
Interestingly, BACE2 is closely related to another enzyme, known as BACE1, involved in producing beta-amyloid.
"Despite their close similarity, the two enzymes have completely opposite effects on beta-amyloid - BACE1 giveth, while BACE2 taketh away," Leissring said in a statement.
The research showed that BACE2 cuts beta-amyloid into smaller pieces, thereby destroying it. Although other enzymes are known to break down beta-amyloid, BACE2 is particularly efficient at this function, the study found.
The researchers will now study whether blocking beta-amyloid destruction by BACE2 can increase the risk for Alzheimer's disease in a mouse model of the disease.