Tipping the Scale from Disorder to Alpha-helix: Folding of Amphiphilic Peptides in the Presence of Macroscopic and Molecular Interfaces
Fig 4
Simulations of a single peptide at the vacuum/water interface for LK (left) and EALA (right).
Simulations are started with random conformations at the center of the water slab. Upon adsorption of peptides (after 45 ns for LK and 50 ns for EALA) partitioning of hydrophobic/hydrophilic residues and folding into the α-helix structure (after 800 ns for LK and 350 ns for EALA) is observed. Snapshots depicting the adsorption and adoption of the α-helix structure (A and B) and the DSSP analysis of the secondary structure evolution (C and D) are shown for both molecules. SASA, intra-peptide backbone hydrogen bonds and short-range Coulomb interaction energies between the charge groups (E and F) display the partitioning of hydrophobic/hydrophilic residues and secondary structure formation in the presence of the interface.