Multiprotein Interactions during Surface Adsorption: a Molecular Dynamics Study of Lysozyme Aggregation at a Charged Solid Surface

Abstract

Multiprotein adsorption of hen egg white lysozyme at a model charged ionic surface is studied using fully atomistic molecular dynamics simulations. Simulations with two, three, and five proteins, in various orientations with respect the surface, are performed over a 100 ns time scale. Mutated proteins with point mutations at the major (Arg128 and Arg125) and minor (Arg68) surface adsorption sites are also studied. The 100 ns time scale used is sufficient to observe protein translations, rotations, adsorption, and aggregation. Two competing processes of particular interest are observed, namely surface adsorption and protein–protein aggregation. At low protein concentration, the proteins first adsorb in isolation and can then reorientate on the surface to aggregate. At high concentration, the proteins aggregate in the solution and then adsorb in nonspecific ways. This work demonstrates the role of protein concentration in adsorption, indicates the residues involved in both types of interaction (protein–protein and protein–surface), and gives an insight into processes to be considered in the development of new functionalized material systems.

Lysozyme adsorption at a silica surface using simulation and experiment: effects of pH on protein layer structure

“…The opposite result suggests that Arg has higher affinity to SiO 2 surface than Lys, nevertheless in both cases the affinity is high. This agrees with other work in the literature regarding the key residues for protein adsorption at charged surfaces [23][24][25][26] and silica nanoparticles. 27 …”

“…Initially the dipole moment direction is changed due to very small conformational changes, and then the prote i ns t a r t st or o t a t et oo r i e n ti t s dipole moment towards the siloxide-rich surface. This exposes the N,C-terminal face, which has been identified as the major adsorption site on negatively charged surfaces, 11,23,24 to the surface, after whichtheproteinstartstotranslate towards the surface. Translation and slow rotation are continued until usually 3-4 anchor residues adsorb, which is typically observed within 4 ns (Table S2, ESI †).…”

Fibronectin Module FNIII9 Adsorption at Contrasting Solid Model Surfaces Studied by Atomistic Molecular Dynamics

“…Therefore only local structural changes are induced by the adsorption, which agrees well with previous MD adsorption studies. [15][16][17][18]21,22,26 Of the anchoring residues, lysine and arginine are positively charged, and serine is polar.…”

“…This observation agrees well with our previous adsorption simulations for lysozyme on mica. [15][16][17][18]21 We have also analyzed the FN Table S4; in general, the FN III 9 regions exposed to the solvent are the N&C-ter and -sheets B1 and B7. The region is acidic and neutral in terms of hydrophobicity.…”

Molecular Dynamics Simulations of a Binary Protein Mixture Adsorption onto Ion-Exchange Adsorbent

“…12,14 Furthermore, MD simulation has been applied in a study on surface adsorption and aggregation of lysozyme. 15 In our former work, 16 MD simulations have been successfully employed to study the single component protein adsorption onto an ion-exchange chromatographic media. The mechanism and the molecular configurations of adsorption were studied, and the results were consistent with experimental data.…”