QPCT and early-onset autosomal dominant Alzheimer disease: This dense arrangement of catechol-type moieties is hypothesized to favor strong binding with metal-dependent enzymes such as human glutaminyl cyclase (hQC), a key contributor to the generation of pyroglutamate-modified amyloid-β (pE-Aβ3-42), which plays a critical role in the pathogenesis of Alzheimer’s disease.