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Title: Site-directed spin labeling-electron paramagnetic resonance spectroscopy in biocatalysis: Enzyme orientation and dynamics in nanoscale confinement
Site-directed spin labeling (SDSL) in combination with electron paramagnetic resonance (EPR) spectroscopy probes the otherwise inaccessible structural information in complex biological systems. We recently extended SDSL-EPR to reveal the relative orientation and backbone dynamics of enzymes upon encapsulation in mesoporous nanostructures, which set the structural basis underlying the observed biocatalytic activity. Our strategy had generated interest in the biocatalysis community, and thus in this resource article, we contribute an introduction to the principles and experimental procedure that generalize SDSL-EPR to heterogeneous biocatalysis. We will focus on enzymes in mesoporous materials with examples demonstrating the methods and cautions of potential pitfalls. The ultimate goal is to provide the biocatalysis community with a powerful resource to fill in a long-standing knowledge gap in heterogeneous biocatalysis and the structure-function relationship of enzymes at the interface of enzyme-mesoporous materials and utilize the structural insights to guide the rational design of porous platforms for enzyme immobilization.
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Chem catalysis
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National Science Foundation
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