Acrylate‐derived RAFT Polymers for Enzyme Hyperactivation – Boosting the α‐Chymotrypsin Enzyme Activity Using Tailor‐Made Poly(2‐Carboxyethyl)acrylate (PCEA)

Abstract

AbstractWe study the hyperactivation of α‐chymotrypsin (α‐ChT) using the acrylate polymer poly(2‐carboxyethyl) acrylate (PCEA) in comparison to the commonly used poly(acrylic acid) (PAA). The polymers are added during the enzymatic cleavage reaction of the substrate N‐glycyl‐L‐phenylalanine p‐nitroanilide (GPNA). Enzyme activity assays reveal a pronounced enzyme hyperactivation capacity of PCEA, which reaches up to 950 % activity enhancement, and is significantly enhanced to PAA (revealing an activity enhancement of approx. 450 %). In a combined experimental and computational study, we investigate α‐ChT/polymer interactions to elucidate the hyperactivation mechanism of the enzyme. Isothermal titration calorimetry reveals a pronounced complexation between the polymer and the enzyme. Docking simulations reveal that binding of polymers significantly improves the binding affinity of GPNA to α‐ChT. Notably, a higher binding affinity is found for the α‐ChT/PCEA compared to the α‐ChT/PAA complex. Further molecular dynamics (MD) simulations reveal changes in the size of the active site in the enzyme/polymer complexes, with PCEA inducing a more pronounced alteration compared to PAA, facilitating an easier access for the substrate to the active site of α‐ChT.