CSAW: a dynamical model of protein folding
نویسنده
چکیده
CSAW (conditioned self-avoiding walk) is a model of protein folding that combines the features of SAW (self-avoiding walk) and the MonteCarlo method. It simulates the Brownian motion of a chain-molecule in the presence of interactions. We begin with a simple model that takes into account the hydrophobic effect and hydrogen bonding. The results show that the hydrophobic effect alone establishes a tertiary structure, which however has strong fluctuations. When hydrogen bonding is added, helical structures emerge, and the tertiary structure becomes more stable. The evolution of the chain exhibits a rapid hydrophobic collapse into a ”molten globule”, whose slow transition to the final equilibrium state mimics experimental data. The model is designed so that one can add desired features step by step.
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