Fig. 1

Phylogenetic tree of 72 plant PAE proteins. The evolutionary history was inferred by using the Maximum Likelihood method based on the JTT matrix-based model [71]. The tree with the highest log likelihood (−22,303.4018) is shown. Initial tree(s) for the heuristic search were obtained automatically by applying Neighbor-Join and BioNJ algorithms to a matrix of pairwise distances estimated using a JTT model, and then selecting the topology with superior log likelihood value. The tree is drawn to scale, with branch lengths measured in the number of substitutions per site. The analysis involved 72 amino acid sequences. All positions with less than 95% site coverage were eliminated. That is, fewer than 5% alignment gaps, missing data, and ambiguous bases were allowed at any position. There were a total of 341 positions in the final dataset. Evolutionary analyses were conducted in MEGA7 [27]. Each major clade is identified with a specific color. Clade 1 is in purple, clade 2 in green, clade 3 in blue, clade 4 in dark red and clade 5 in pink