Fig. 3.—

Phylogenetic tree of mycobacterial ESX loci from concatenated sequences of EccB, EccC, and MycP. Red circles: plasmid-borne ESX types. Dotted red circles: putative ESX-containing plasmids. Green boxes: Nocardia farcinica and Gordonia bronchialis. Best evolution model identified by MEGA software (WAG+G+I). Tree constructed with maximum-likelihood method with 250 bootstrap replications. Values > 70% are indicated. Note that for some species only selected chromosomal ESX systems are shown, as defined in supplementary table S1, Supplementary Material online. RGM, rapidly growing mycobacteria; SGM, slowly growing mycobacteria.