Molecular dynamics of helical m-phenylene ethynylene foldamer with PEG side chains

COMP 190

One-Sun Lee, one@sas.upenn.edu and Jeffery G. Saven. Department of Chemistry, University of Pennsylvania, 231 S. 34 street, Philadelphia, PA 19104
The folded states of 18-monomer oligo(m-phenylene ethynylene) foldamers (mPE) with polyethylene glycol (PEG) side chains solvated in water are examined using NpT molecular dynamics simulation. The helical parameters are comparable to those of mPE without side the PEG chains in a previous study, but the number of water molecules inside the cavity of mPE is reduced. The cavity of mPE is occupied by the PEG side chains instead of water molecules. The mean value of the number of side chains threaded inside the cavity is 2. The helical structure of backbone is maintained and the turns of the helix are in close contact during the simulation. The simulations reveal how the flexibility of PEG groups facilitates the solvation of complex molecular surfaces.