Figure 1.

Dendrogram summarizing sequence groupings and branching patterns of EPKs derived from the phenogram. The program TreeExplorer was used to edit the main phenogram (see Additional data files), collapsing branches composed entirely of sequences that cluster with one another. Branch nomenclature was guided by previously accepted subfamily nomenclature, but differs from the classical subfamily nomenclature where justified by the structure of the phenogram. Sequences that do not clearly belong to a particular cluster were left in the figure as singletons. Because no branch lengths were specified for partial sequences present in the phenogram, and because only a portion of the catalytic domain of these sequences is available for comparison, assigning partial sequences to clusters would have been subject to significant error, and was not attempted. Partial sequences are therefore not included in this figure. Subfamilies are labeled in red, while singletons are labeled in blue. The relationship between each EPK, the assigned branch names, and the classical subfamily nomenclature is presented in the EPK data table (see Additional data files).