Fig. 3: Coverage of homology modelling vs. sequence identity
The accuracy of homology modelling depends on the level of pairwise sequence identity between the protein to be modelled (U) and the template (T) of known structure. Above 90% sequence identity homology modelling reaches the accuracy of structure determination; at this level about 4% of the SWISS-PROT proteins (i.e. 1,900) can be modelled. Down to levels of about 70% identity, i.e., for about 11% of SWISS-PROT (4,600 sequences), homology modelling can still provide rather accurate models.
