The bacterial plant pathogen genus Xanthomonas uses two distinct secretion systems for antibacterial competition. Here the authors show that some Xanthomonas lineages have switched from the ancestral X-T4SS state to T6SS-i4 despite the functional similarity of the systems, with X-T4SS gene clusters subject to degradation and loss and T6SS-i4-encoding sequences inserted through independent gains.
- Chloé Peduzzi
- Jules Butchacas
- Claude Bragard
