ANGLOR: A Composite Machine-Learning Algorithm for Protein Backbone Torsion Angle Prediction

作者：Wu Sitao^*; Zhang Yang

来源：PLos One, 2008, 3(10): e3400.

DOI：10.1371/journal.pone.0003400

We developed a composite machine-learning based algorithm, called ANGLOR, to predict real-value protein backbone torsion angles from amino acid sequences. The input features of ANGLOR include sequence profiles, predicted secondary structure and solvent accessibility. In a large-scale benchmarking test, the mean absolute error (MAE) of the phi/psi prediction is 28 degrees/46 degrees, which is similar to 10% lower than that generated by software in literature. The prediction is statistically different from a random predictor (or a purely secondary-structure-based predictor) with p-value <1.0X10(-300) (or <1.0X10(-148)) by Wilcoxon signed rank test. For some residues (ILE, LEU, PRO and VAL) and especially the residues in helix and buried regions, the MAE of phi angles is much smaller (10-20 degrees) than that in other environments. Thus, although the average accuracy of the ANGLOR prediction is still low, the portion of the accurately predicted dihedral angles may be useful in assisting protein fold recognition and ab initio 3D structure modeling.

• 出版日期2008-10-15
• 单位上海生物信息技术研究中心