Recent studies highlight that bacterial pathogens can reprogram target cells by influencing epigenetic factors. The type III secretion system (T3SS) is a bacterial nanomachine that resembles a syringe on the bacterial surface. The T3SS 'needle' delivers translocon proteins into eukaryotic cell membranes, subsequently allowing injection of bacterial effectors into the cytosol. Here we show that Pseudomonas aeruginosa induces early T3SS-dependent dephosphorylation and deacetylation of histone H3 in eukaryotic cells. This is not triggered by any of the P. aeruginosa T3SS effectors, but results from the insertion of the PopB-PopD translocon into the membrane. This suggests that the P. aeruginosa translocon is a genuine T3SS effector acting as a pore-forming toxin. We visualized the translocon plugged into the host cell membrane after the bacterium has left the site of contact, and demonstrate that subsequent ion exchange through this pore is responsible for histone H3 modifications and host cell subversion.

中文翻译：

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铜绿假单胞菌III型分泌系统的转座子的毛孔形成活动改变了宿主表观基因组。

最近的研究强调细菌病原体可以通过影响表观遗传因素来重编程靶细胞。III型分泌系统（T3SS）是一种细菌纳米机器，类似于细菌表面上的注射器。T3SS的“针”将translocon蛋白递送到真核细胞膜中，随后将细菌效应子注射到细胞质中。在这里，我们显示铜绿假单胞菌诱导真核细胞中组蛋白H3的早期T3SS依赖的去磷酸化和去乙酰化。这不是由任何铜绿假单胞菌T3SS效应子触发的，而是由PopB-PopD转座子插入膜中引起的。这表明铜绿假单胞菌转座子是真正的T3SS效应子，可作为造孔毒素。