Fig. 2.

Phylogeny and organization of the T6SS gene cluster. The maximum likelihood phylogeny was inferred based on a concatenated alignment (5960 aligned amino acid sites) of 14 core T6SS genes, including tagE, tagF, tssM, tssL, tssK, tagH, tssG, tssF, tssE, tagJ, tssC40, tssC41, tssB, and tssD. Two other core genes, tssA and tssH, are excluded because some homologs are pseudogenized. Genes downstream of tssD (e.g., tai, tae, and vgrG) are excluded due to variable presence. The species phylogeny on the right is based on Fig. 1. Genes are color-coded according to annotation, and syntenic regions are indicated by gray blocks