While the peptide variant analysis in Figure attests to the significance of positive fibrils surface charge, the less pronounced catalytic activity of PFR fibrils in comparison with PFK point to the key roles of the lysine sidechains in inducing catalysis. This observation is supported by the MD simulations highlighting the significance of K8, K10, and K12 in anchoring the β-lactam substrate on the PFK amyloid fibril surface. The lysine arrays likely create high local cationic charge on the fibril surface, enhancing immobilization of the anionic β-lactam molecules on the fibril surface.