Figure 1.

Phylogenetic relationship of representative mec allotypes. Nucleotide sequences were aligned using MUSCLE, with the maximum likelihood method, based on the general time reversible model, being used to build the tree. The highest log likelihood ( − 9785.4010) tree is shown. The percentage of trees in which the associated genes clustered together, based on bootstrapping with 500 replicates, is shown at the branches. A discrete gamma distribution was used to model site substitution rates, with branch lengths measured in the number of substitutions per site.