Effects of glycosylation on the structure of Glucose oxidase

Dimuthu Kodituwakku

University of Florida

Glucose Oxidase (GOx)is an enzyme widely used in biosensors. The dimeric structure of GOx is known to be catalytically active. The retention of GOx's catalytic activity is dependent on this dimeric structure. However, it has been observed that removing the glycans or deglycosylation of glycoproteins can enhance electron transfer and current density in proteins, including GOx. Therefore, our study aimed to investigate the impact of removing glycans on the dimeric structure of GOx through atomistic molecular dynamics simulations.Our analysis involved comparing the deglycosylated (~14 μs) and glycosylated (~8 μs) systems of GOx under standard conditions. The findings revealed that removing glycans resulted in increased rotations, tilting, and distance between the interaction regions of the two monomers interfaces compared to glycosylated GOx. Additionally, we discovered that the interfacial glycans interacted preferentially with residues of the adjacent monomer. Specifically, the glycan located at ASN93 showed preferential contacts with a range of residues, including aromatic (PHE488, TYR496), hydrogen bonding (GLY490, GLU491, GLY495, THR492, ASN497), and aliphatic (LEU493, PRO494) residues.