Figure 6: A Neighbor-Joining phylogenetic tree of glutathione S-transferase (GST) amino acids sequences with three types representing phi, tau, and zeta classes. Phi and tau are plant-specific GSTs. Bootstrap values from 1,000 replicates were used to assess the robustness of the trees. Only bootstrap values above 75% are indicated at the nodes. Accession numbers for genes from other species are given in Supplementary data.