Improving the Prediction of Protein-Protein Interaction Sites Using a Novel Over-Sampling Approach and Predicted Shape Strings.

Identification of protein-protein interaction (PPI) sites is one of the most challenging tasks in bioinformatics and many computational methods based on support vector machines have been developed. However, current methods often fail to predict PPI sites mainly because of the severe imbalance between the numbers of interface and non-interface residues. In this study, we propose a novel over-sampling method that relaxes the class-imbalance problem based on local density distributions. We applied the proposed method to a PPI dataset that includes 2,829 interface and 24,616 non-interface residues. The experimental result showed a significant improvement in predictive performance comparing with the other state-of-the-art methods according to the six evaluation measures.