Lattice heteropolymers, protein folding models

The fact that the folding (and unfolding) kinetics of relatively small, two-state proteins can be predicted with reasonable accuracy from global features of the native state like the contact order, stability, and number of contacts supports the idea that the details of protein structure are not required to capture the key features of protein folding, so that reduced representations should be adequate. However, the most widely used simple heteropolymer models, those restricted to a simple cubic lattice, predict that stability is more important than native structure, in contrast to the experimental data for proteins. In this section we seek to understand why lattice models differ from proteins in this regard. Doing so is of importance because complete details of the folding trajectories of such models... 

Enumeration is a powerful method for the investigation of some interesting features of heteropolymer folding in an evolutionary context, because it creates exact data. However, it is obviously only applicable to small lattice systems. The investigation of longer chains and more specific models requires more sophisticated stochastic approaches, which unfortunately can only generate approximate results. We will introduce some of the standard methods in the following chapter, before we return to the discussion of structural properties of polymers and proteins. 

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