Ou Yu-Yen, Gromiha M Michael, Chen Shu-An, Suwa Makiko
Department of Computer Science and Engineering, Yuan Ze University, Chung-Li, Taiwan.
Comput Biol Chem. 2008 Jun;32(3):227-31. doi: 10.1016/j.compbiolchem.2008.03.002. Epub 2008 Mar 18.
Discriminating outer membrane proteins (OMPs) from other folding types of globular and membrane proteins is an important task both for identifying OMPs from genomic sequences and for the successful prediction of their secondary and tertiary structures. We have developed a method based on radial basis function networks and position specific scoring matrix (PSSM) profiles generated by PSI-BLAST and non-redundant protein database. Our approach with PSSM profiles has correctly predicted the OMPs with a cross-validated accuracy of 96.4% in a set of 1251 proteins, which contain 206 OMPs, 667 globular proteins and 378 alpha-helical inner membrane proteins. Furthermore, we applied our method on a dataset containing 114 OMPs, 187 TMH proteins and 195 globular proteins obtained with less than 20% sequence identity and obtained the cross-validated accuracy of 95%. This accuracy of discriminating OMPs is higher than other methods in the literature and our method could be used as an effective tool for dissecting OMPs from genomic sequences. We have developed a prediction server, TMBETADISC-RBF, which is available at http://rbf.bioinfo.tw/~sachen/OMP.html.
区分外膜蛋白(OMP)与其他折叠类型的球状蛋白和膜蛋白,对于从基因组序列中识别OMP以及成功预测其二级和三级结构而言,都是一项重要任务。我们基于径向基函数网络以及由PSI-BLAST和非冗余蛋白质数据库生成的位置特异性得分矩阵(PSSM)谱,开发了一种方法。在一组包含206个OMP、667个球状蛋白和378个α-螺旋内膜蛋白的1251种蛋白质中,我们使用PSSM谱的方法以96.4%的交叉验证准确率正确预测了OMP。此外,我们将我们的方法应用于一个数据集,该数据集包含114个OMP、187个跨膜螺旋(TMH)蛋白和195个序列同一性低于20%的球状蛋白,并获得了95%的交叉验证准确率。这种区分OMP的准确率高于文献中的其他方法,并且我们的方法可作为从基因组序列中剖析OMP的有效工具。我们开发了一个预测服务器TMBETADISC-RBF,可在http://rbf.bioinfo.tw/~sachen/OMP.html获取。