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Welcome to H-Predictor Hinge-Region Prediction Service
Hinge region predictor (H-Predictor) predicts putative hinge regions involved in protein oligomerization via the domain-swapping mechanism. Domain swapping is an important mechanism for protein oligomerization, in which a fragment of a protein exchanges with a corresponding fragment of another like protein. The segment of polypeptide chain that links the swapped domain and the main protein is the hinge region. In most experimentally observed domain-swapped oligomers, the swapped domains correspond to one or several secondary structural elements from either the N- or C-termini. Only in some rare instances the swapped domains are positioned in the middle of the protein. The domain-swapped oligomeric structures are, therefore, mainly determined by the location and the properties of the hinge region.
Using a simple contact-based potential for enthalpy and graph theory- based estimation for entropy, H-Predictor quantifies for each residue the propensity as the hinge region. Physically, the H-Predictor computes for each residue the effective temperature to populate an "intermediate" sate, where the protein unfolds around this residue into two sub-domains each of which maintains their native-like structure. Thus, the smaller the effective temperature, the higher the probability for a residue to be in the hinge-region. The proposed predictor is not a measure of the protein's propensity for domain-swapping, but rather a structural propensity that a hinge region may result in domain swapping. Additionally, if the protein features folding intermediate, the H-Predictor can also provide hint to the weakest regions that unfold prior to the compete unfolding. For details of the method, please refer to the paper (F. Ding, K. C. Prutzman, S. L. Campbell, and N. V. Dokholyan, Structure, 14: 5-14 (2006))