Kinetics study of Bungarus fasciatus venom acetylcholinesterase immobilised on a Langmuir-Blodgett proteo-glycolipidic bilayer

摘要

This study deals with the kinetics properties of an enzyme immobilised in a defined orientation in a biomimetic environment. For this purpose, acetylcholinesterase (AChE) was captured at the surface of a nanostructured proteo-glycolipidic Langmuir-Blodgett film through specific recognition by a noninhibitor monoclonal antibody (IgG) Inserted in a neoglycolipid bilayer. Modelling of this molecular assembly provided a plausible interpretation of the functional orientation of the enzyme. The AChE activity being stable for several weeks, the enzyme kinetics were investigated, and fitted perfectly with heterogeneous biocatalytic behaviour representative of cellular enzymatic catalysis, The AChE-IgG-glycolipid nanostructure was directly interfaced with an efficient optical device. Such an association, leading to an intimate contact between the nanostructure and the biochemical signal transducer, gives direct access to the intrinsic AChE behaviour. This study thus demonstrates the potential for direct investigation of the kinetic behaviour of an immobilised enzyme on a lipid bilayer through an efficient transduction system.