Effects of the Hydrophobicity of Key Residues on the Characteristics and Stability of Glucose Oxidase on a Graphene Surface

Abstract

Glucose oxidase (GOx) is one of the most widely investigated enzymes in the field of bioelectrochemistry. It is mainly used for the detection of glucose in solutions and enzyme-based biofuel cells. On the basis of the combination of GOx with graphene, novel nanodevices exceeding conventional limits can be developed. To develop a hybrid enzyme–graphene nanodevice with a good performance, it is important that GOx is deposited well on the graphene surface while maintaining its structure and not impeding the oxidation activity of the GOx. In this study, we propose a method to improve the stability of GOx and secure its immobility on the graphene sheet and its glucose-binding affinity by single-point mutation of GOx using molecular dynamics simulations. We confirm that the structural stability, immobility, and substrate binding affinity of GOx can be modified by changing the hydrophobicity of a key residue. We demonstrate that biosensors or biofuel cells can be redesigned and their properties can be improved by using molecular dynamics simulation.

Identification of key amino acid residues toward improving the catalytic activity and substrate specificity of plant-derived cytochrome P450 monooxygenases CYP716A subfamily enzyme for triterpenoid production in Saccharomyces cerevisiae

“…This would also affect the ability of the enzyme to generate enormous variation in its catalytic activity and substrate specificity. Altering the properties of important residues and the environment surrounding the ligand-binding site may significantly affect substrate recognition, and binding may affect the catalytic activity (Narayan et al, 2015;Blaha-Nelson et al, 2017;Li et al, 2017;Baek et al, 2020;Sun et al, 2020). We hypothesized that altering the docking profile would affect substrate recognition, thereby affecting the binding pocket and triterpene backbone interaction and, in turn, the catalytic activity of enzyme.…”

Silk-based organic photoresists for extreme ultraviolet lithography: a multiscale in silico study

“…31 Our previous studies using an in silico method have provided insight into the interfacial surface behavior of biomolecules. [30][31][32] Using QM simulations, we replicated the Auger effect-induced photoreactions in the silk peptide biopolymer-based PR material to investigate its electronic behavior after EUV exposure. In addition, the QM parameters were incorporated in the MD simulations to evaluate the aggregation properties of silk peptides.…”

Reduced Graphene Oxide and Polyaniline Nanofibers Nanocomposite for the Development of an Amperometric Glucose Biosensor

“…In addition, higher electrical conductivity leads to hydrophobic properties of the rGO surface. Since the structural stability, immobilization efficiency, and substrate binding affinity of glucose oxidase (GOx) depend on the hydrophobicity of the substrate [ 13 ], the employment of rGO nanocomposites is a key factor for the maintenance of immobilized GOx activity, keeping the positive effect of rGO on the biosensor analytical signal [ 14 , 15 ].…”