How Does Varying Sizes and Concentrations of Poly(Ethylene Glycol) Affect the Conformation and Function of the Enzyme Escherichia Coli Prolyl-Trna Synthetase?

Abstract

Poly(ethylene glycol) (PEG) is a biocompatible, hydrophilic, flexible, non-toxic polyether commonly used in proteomics because it is widely regarded to be a biologically inert molecule. This includes PEG2000 (molecular weight of 2000g/mol), which is a component in the Pfizer-BioNTech and Moderna COVID-19 vaccines. However, recent studies suggest that PEG may impact protein function, depending largely on the molecular weight of the PEG. In this study, we observe the effects of PEG on the function and conformation of enzyme prolyl-tRNA synthetase of Escherichia coli (Ec ProRS). ProRS catalyzes the covalent attachment of proline to tRNAPro and thus is essential for protein biosynthesis. The molecular mechanism of PEG-protein interactions has been probed using enzyme kinetics, fluorescence spectroscopy, and molecular modeling. Herein, we present the results of our study.