Machine learning and data mining methods have been widely used in the computational biology and bioinformatics area. Many researchers have made lots of efforts to develop useful algorithms and softwares to investigate various drug-related biological problems, such as HIV protease cleavage site prediction [18, 19] , identification of GPCR (G protein-coupled receptors) type [20, 21] , protein signal peptide prediction [22] , protein subcellular location prediction [23, 24, 25] , analysis of specificity of GalNAc-transferase protein [26] , identification of protease type [27, 28] , membrane protein type prediction [29, 30, 31, 32] , and a series of relevant webserver predictors as summarized in a recent review [33] .