4.4 Predicting conformation from sequence
Given the amino acid sequence of a protein, it is possible to use computational methods to try to fit the sequence into folding patterns. This operation is called ‘threading’. Different conformations can be ranked according to how well they accommodate the sequence; that is, the most stable conformation is ranked highest. Of course, this technique can only be used for those folds that have been definitively described by X-ray diffraction or NMR, and the structure of those proteins whose sequence does not conform to the restrictions of any known folding patterns must be determined experimentally.