Amyloid, composed largely of mis-folded proteins that form insoluble fibrillar aggregates, is important to many human diseases including Alzheimer’s. Tooth decay also features amyloid-forming proteins, but in this case it is not mis-folded human amyloid proteins but bacterial proteins that are not mis-folded when they aggregate into functional amyloid polymers. The most common infectious disease in humans, tooth decay, involves the formation of microbial communities in biofilms on teeth.
