Molecular Dynamics Simulation of Protein Adsorption at Fluid Interfaces: A Comparison of All-Atom and Coarse-Grained Models

The adsorption of LTP at the decane-water interface. was modeled using all-atom and coarse-grained (CC) molecular dynamics simulations. The CC, model (300 us simulation, 1200 us scaled time) generates equilibrium adsorbed conformations in about 12 h, % whereas the equivalent 1200 ns simulation would take about 300 days for the all-atom model. in both models the LIT molecule adsorbs with alpha-helical regions parallel to the interlace with an average tilt angle normal 19 the interface of 73 degrees for the all-atom model and 62 degrees for the CG model. In the all-atom model, the secondary, structure of the LTP is conserved upon adsorption. A considerable proportion of the N-terminal loop of LTP can be found in the decane phase for the all-atom model, whereas in the CC, model the protein only penetrates as far as the mixed water-decane interfacial region. This difference may arise due to the different schemes used to parametrize force field parameters in the two models.