Molecular Simulation Of Protein Adsorption On Solid-liquid Interfaces

Protein adsorption on interface is a common phenomena and a key to settle problems of surface science,biological science and engineering systems which is of great fundamental and practical importance. The complexity interaction between protein and surface make it impossible to get complete adsorption information only using experiment method. It is helpful to grasp protein adsorption mechanism using molecular simulation at the molecular level research. In this work, we focus on poly-ten-lysine interactions with several interfaces by MD techniques in which protein is modeled with the CHARMM22 parameter set, water molecules are described by the transferable intermolecular potentials with three-site point charge model (TIP3P), under NVT condition and the surfaces were platinum (Pt), znic oxide (ZnO) and polyethylene (PE). The influences of properties studied include the interface properties (interface structural and electrostriction nature), dynamic behavior of aqueous and different force field factors'influence during adsorption. Analyze the conformation, energy and motion of poly-ten-lysine. Discuss the mechanisms of poly-ten-lysine adsorption on solid-liquid interface.Results reveal the interaction between poly-ten-lysine and interfaces make theα-helix conformation of poly-ten-lysine decrease to different extent. More distinct decrease even denatured happened on PE interfaces than Pt and ZnO interfaces. Besides, interface structural has important influence on adsorption. On different crytral lattic Pt interfaces, the more impact arrangement it is, the more stronger interaction between interface and poly-ten-lysine. The interaction between the protein and crystal interface is stronger than amorphous interface.MD simulations on interfaces with different van der Waals parameters and charge show that interface interaction is to be dominated by electrostatic force interactions and van der Waals relatively weaker though they all affected adsorption conformation of poly-ten-lysine.The interaction between the poly-ten-lysine and ZnO interface is mediated by aqueous. Interface interaction is the result of mutual interaction of the constituent elements of system, poly-ten-lysine, water and interface. Accordingly, hydrophobic nature of interface play an important role during adsorption, hydrophobic PE interfaces have stronger affection on protein conformation than hydrophilic interface. Moreover, energy compositions and atom parameter of force field play an important role in simulation.The molecular simulating results could offer theoretical basic for protein adsorption on interface and promote the development of related technology.To better analyze results, another force field is used to the same interface condition which indicate that atom parameters of force field and energy items are the important factors that influence the simulation.