Symmetry Recurrence in protein sequence and structure with Pearson´s correlation coefficients

Evidence suggests that the present complex proteins may evolved from short peptide ancestors through a series of gene duplication and fusion events. In this paper, we use a modified recurrence plot method combined with Pearson correlation and dRMSD analysis to study the internal repeats in sequence and structure of left handed beta helix (LβH) fold and beta prism fold. Through our study, we find that most of the proteins in LβH fold reveal twofold repeats in both the sequence and structure, whereas only sequences of the proteins from beta prim fold show threefold repeats and the threefold repeats signal in structure is not weak. This may give some insights for the protein evolution.