Figure 1

Genetic organization of the different type VI secretion gene clusters (T6SS) in Pantoea ananatis (PA). Genes are indicated by arrows and the direction of the arrows represents the direction of transcription of the gene related to the rest of the genome. We used the type VI secretion system gene nomenclature of Shalom et al. [50]. Conserved core gene components of the T6SS (tssA-M) are indicated in red while non-conserved genes associated with the T6SS of limited bacteria (tagA-P) are indicated in different colors. The tag genes found in the T6SS gene clusters of other bacteria are indicated in the key. The figure is not drawn to scale, PA T6SS-1 and PA T6SS-2 are both over 30 kb and contain up to 20 genes each, while PA T6SS-3 (9 kb) contains 8 genes in all sequenced strains.