title: Molecular Dynamic Studies of the Complex Polyethylenimine and Glucose Oxidase.
abstract: Glucose oxidase (GOx) is an enzyme produced by Aspergillus, Penicillium and other fungi species. It catalyzes the oxidation of β-d-glucose (by the molecular oxygen or other molecules, like quinones, in a higher oxidation state) to form d-glucono-1,5-lactone, which hydrolyses spontaneously to produce gluconic acid. A coproduct of this enzymatic reaction is hydrogen peroxide (H₂O₂). GOx has found several commercial applications in chemical and pharmaceutical industries including novel biosensors that use the immobilized enzyme on different nanomaterials and/or polymers such as polyethylenimine (PEI). The problem of GOx immobilization on PEI is retaining the enzyme native activity despite its immobilization onto the polymer surface. Therefore, the molecular dynamic (MD) study of the PEI ligand (C14N8_07_B22) and the GOx enzyme (3QVR) was performed to examine the final complex PEI-GOx stabilization and the affinity of the PEI ligand to the docking sites of the GOx enzyme. The docking procedure showed two places/regions of major interaction of the protein with the polymer PEI: (LIG1) of -5.8 kcal/mol and (LIG2) of -4.5 kcal/mol located inside the enzyme and on its surface, respectively. The values of enthalpy for the PEI-enzyme complex, located inside of the protein (LIG1) and on its surface (LIG2) were computed. Docking also discovered domains of the GOx protein that exhibit no interactions with the ligand or have even repulsive characteristics. The structural data clearly indicate some differences in the ligand PEI behavior bound at the two places/regions of glucose oxidase.
authors: Department of Physical Chemistry, Faculty of Pharmacy, Collegium Medicum, Nicolaus Copernicus University, Kurpinskiego 5, 85-096 Bydgoszcz, Poland. beatas@cm.umk.pl.
authors: Beata
authors: B
authors: Szefler
authors: Department of Chemistry, Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, 400028 Cluj-Napoca, Romania. diudea@gmail.com.
authors: Mircea V
authors: MV
authors: Diudea
authors: Laboratory of Structural and Computational Physical-Chemistry for Nanosciences and QSAR, Biology-Chemistry Department, West University of Timisoara, Str. Pestalozzi No. 16, 300115 Timisoara, Romania. mv_putz@yahoo.com.|Laboratory of Renewable Energies-Photovoltaics, R&D National Institute for Electrochemistry and Condensed Matter (INCEMC), Dr. A. Paunescu Podeanu Str. No. 144, 300569 Timisoara, Romania. mv_putz@yahoo.com.
authors: Mihai V
authors: MV
authors: Putz
authors: Department of Pharmaceutical Nanotechnology and Nanotoxicology, Faculty of Pharmacy, Medical University of Warsaw, 02-097 Warsaw, Poland. ireneusz.grudzinski@wum.edu.pl.
authors: Ireneusz P
authors: IP
authors: Grudzinski
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology; D002384:Catalysis; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005947:Glucose / Q000378:metabolism; D005949:Glucose Oxidase / Q000737:chemistry* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry; D008024:Ligands; D046911:Macromolecular Substances / Q000737:chemistry* / Q000378:metabolism; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D010084:Oxidation-Reduction; D011094:Polyethyleneimine / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation
chemical_list: D004800:Enzymes, Immobilized; D008024:Ligands; D046911:Macromolecular Substances; D011094:Polyethyleneimine; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D005947:Glucose
keywords: 3QVR; docking; glucose oxidase (GOx); molecular dynamics; polyethylenimine (PEI)