Gold nanoparticles capable of templating entire enzyme cascades and improving production yield through substrate channeling

Abstract

We have demonstrated that multi-enzyme cascades can be templated on individual gold nanoparticles (NPs) with diameters below 100 nm. Utilizing a three enzyme cascade of amylase, maltase, and glucokinase we found a ~3-fold enhancement in product formation when all three enzymes were bound to the same NP as compared to controls. This strongly suggests that the increased kinetics was due to substrate channeling. Additional controls were realized to ensure that only when the enzymes were bound to the NPs was enhancement observed by modifying the ratio of enzyme to NP. Furthermore the experiments support a model where a single-layer of enzymes conjugate to the NPs independently of the enzyme to NP ratio. Being able to conjugate entire cascades on individual NPs should allow for optimized design of NPs and enzyme cascades for in vitro biocatalysis.