Figure 2.
Phylogenetic tree of selected ArgR sequences. The three major branches are colored: green is defined by MtArgR and is closest in evolutionary distance to the common ancestor (scale bar, bottom, average number of residue substitutions per position); orange is defined by BsArgR; and yellow is defined by EcArgR. Entries shown in grey represent sequences that belong to the assigned phylogenetic group but lack the corresponding sequence motif.
