Determination of Interaction Potentials of Amino Acids from Native   Protein Structures: Test on Simple Lattice Models
  We propose a novel method for the determination of the effective interaction potential between the amino acids of a protein. The strategy is based on the combination of a new optimization procedure and a geometrical argument, which also uncovers the shortcomings of any optimization procedure. The strategy can be applied on any data set of native structures such as those available from the Protein Data Bank (PDB). In this work, however, we explain and test our approach on simple lattice models, where the true interactions are known a priori. Excellent agreement is obtained between the extracted and the true potentials even for modest numbers of protein structures in the PDB. Comparisons with other methods are also discussed. 
Jort van Mourik, Cecilia Clementi, Amos Maritan, Flavio Seno, J.R.   Banavar