(397bb) Protein-Mimetic Inhibition of Enzyme Activity By Nanoparticles

Enzyme inhibitors are as ubiquitous as enzymes and are central to wide spectrum of clinical and technological problems. Enzyme inhibitors are typically viewed as organic molecules with inter-molecular lock-and-key matches to sites of target substrates. Unconventional approaches to new enzyme inhibitor designs are required to circumvent biodegradation as well as to develop new momentum and impart new findings to the field. Based on the general nanoparticle-protein analogy, we hypothesized inorganic nanoparticles with specific shapes can be efficient enzyme inhibitor surrogates. We verified the hypothesis through inhibition activity and kinetics of ß-galactosidase (GAL) by ZnO nanoparticles of different shapes. Amongst the ZnO nanoparticles, which include nanospheres, nanoplates and nanopyramids, the inhibition was the strongest for ZnO nanopyramids. Such originated from the geometrical and chemical match between their apexes and grooves on GAL’s surface thereby mimicking biomacromolecular inhibitors. These findings open the road for nanoscale engineering of NPs to fit specific enzymes with biotechnological or biomedical relevance.