Molecular dynamics simulation of egf and tgf-α: Conformation and receptor binding properties

Three 1 ns-long molecular dynamics (MD) simulations were performed on murine epidermal growth factor (mEGF), human epidermal growth factor (hEGF) and human transforming growth factor-alpha (hTGF-α) to obtain further information about their conformational properties. The initial structures were taken based on NMR spectroscopy data and were energy-minimized before MD simulations. No major conformational transitions were observed during simulations. Domain movements, predictable from the mitten model of EGF, were observed only in the simulation of hTGF-α and could account for its different receptor binding properties. Inter-domain interactions, not revealed by the NMR data, were observed between aromatic side-chains for each of the polypeptides and seem to stabilize the conformation necessary for binding.