Protein Surface Structural Recognition in Inactive Areas: A New Immobilization Strategy for Acetylcholinesterase

Abstract

This work reported a new method of design for the immobilization of acetylcholinesterase (AChE) based on its molecular structure to improve its sensitivity and stability. The immobilization binding site on the surface of AChE was determined using MOLCAD's multi-channel functionality. Then, 11 molecules ((+)-catechin, (-)-epicatechin, (-)-gallocatechin, hesperetin, naringenin, quercetin, taxifolin, (-)-epicatechin gallate, flupirtine, atropine, and hyoscyamine) were selected from the ZINC database (about 50 000 molecules) as candidate affinity ligands for AChE. The fluorescence results showed that the binding constant K between AChE and the ligands ranged from 0.01344 × 10 to 4.689 × 10 M and there was one independent class of binding site for the ligands on AChE. The AChE-ligand binding free energy ranged from -12.14 to -26.65 kJ mol. Naringenin, hesperetin, and quercetin were the three most potent immobilized affinity ligands. In addition, it was confirmed that the binding between the immobilized ligands only occurred at a single site, located in an inactive area on the surface of AChE, and did not affect the enzymatic activity as shown through a competition experiment and enzyme assay. This method based on protein surface structural recognition with high sensitivity and stability can be used as a generic approach for design of the enzyme immobilization and biosensor development.

Sustainable Biosynthesis of Esterase Enzymes of Desired Characteristics of Catalysis for Pharmaceutical and Food Industry Employing Specific Strains of Microorganisms

“…A prodrug with an ester linkage can also be used to deliver two active drugs; this technique was used in the synthesis of many prodrugs that have anti-inflammatory, analgesic, and antipyretic properties. The acetylcholinesterase (AChE) has been studied in immobilised form [102] with enhanced enzymatic performances for biosynthesis of esters. The possibility of biodiesel production by reactions catalysed by immobilised AChE could be an interesting option for a new biodiesel technology.…”