A two-stage SVM architecture for predicting the disulfide bonding state of cysteines

P. Frasconi1, A. Passerini1, A. Vullo1
1Dipartimento di Sistemi e Informatica, Università di Firenze, Italy

Tóm tắt

Cysteines may form covalent bonds, known as disulfide bridges, that have an important role in stabilizing the native conformation of proteins. Several methods have been proposed for predicting the bonding state of cysteines, either using local context or using global protein descriptors. In this paper we introduce an SVM based predictor that operates in two stages. The first stage is a multi-class classifier that operates at the protein level. The second stage is a binary classifier that refines the prediction by exploiting local context enriched with evolutionary information in the form of multiple alignment profiles. The prediction accuracy of the system is 83.6% measured by 5-fold cross validation, on a set of 716 proteins from the September 2001 PDB Select dataset.

Từ khóa

#Support vector machines #Bonding #Amino acids #Proteins #Bridges #Neural networks #Electronic mail #Support vector machine classification #Accuracy #Genomics

Tài liệu tham khảo

10.1002/bip.360221211 10.1109/72.788642 leslie, 2002, The spectrum kernel: A string kernel for SVM protein classification, Proc Pacific Symposium on Biocomputing, 564 10.1002/prot.10047 passerini, 2002, From Margins to Probabilities in Multiclass Learning Problems, Proc 15th European Conf on Artificial Intelligence platt, 2000, Probabilistic Outputs for Support Vector Machines and Comparisons to Regularized Likelihood Methods, Advances in Large Margin Classifiers 10.1093/nar/25.1.226 vapnik, 1998, Statistical Learning Theory 10.1162/089976602753633402 bridle, 1989, Probabilistic interpretation of feedforward classification network outputs, with relationships to statistical pattern recognition, Neuro-computing Algorithms Architectures and Applications 10.1002/(SICI)1097-0134(19990815)36:3<340::AID-PROT8>3.0.CO;2-D 10.1093/bioinformatics/17.10.957 10.1002/pro.5560030317 10.1093/bioinformatics/16.3.251 boutilier, 1996, Context-specific independence in Bayesian networks, Proc 12th Conf Uncertainty in Artificial Intelligence, 115 bousquet, 2002, Stability and Generalization, Journal of Machine Learning Research, 2 10.1162/neco.1991.3.1.79