Abstract
Prediction of epitope has great importance in the development of vaccine, drug and peptide libraries and immunologic research. There are very few methods for the prediction of patches containing conformational epitopes, and ninety percent of the epitopes are of conformational type. In this paper, an attempt has been made to propose soft support vector machine model based on the evaluation of different combinations of six scoring functions to predict patches containing conformational epitope. These scoring functions are based on structural properties. The model is implemented on antigen antibody complexes taken from the RCSB protein data bank. This model gives area under curve (AUC) value of 0.6524 which is greater than the AUC value of the existing methods. On evaluation of scoring functions, all scoring functions together give the best results with the highest accuracy of 61.456 for soft SVM and 57.738 for ordinary SVM. This difference in accuracy is due to uncertainty present in the data which ordinary SVM is not able to handle properly. The soft set-based approach incorporates the uncertainty due to parameters in the soft SVM model and leads to improvement in the accuracy of results. These combinations also show the highest sensitivity and Matthews’s correlation coefficient value and F score for soft SVM as compared to ordinary SVM. On the basis of results, it is concluded that the solvation potential, accessible surface area and planarity score have a major correlation with conformational epitope and the combination is recommended for building soft SVM model for prediction of patches containing conformational epitope.
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Singh, C., Adlakha, N. Scoring function-based soft support vector machine model for prediction of patches containing conformational epitope. Netw Model Anal Health Inform Bioinforma 5, 2 (2016). https://doi.org/10.1007/s13721-015-0109-y
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DOI: https://doi.org/10.1007/s13721-015-0109-y