Robatzek lab: Our first publication on extracellular vesicles from bacteria and their interaction with plants is available.
Biophysical and proteomic analyses suggest functions of Pseudomaonas Syringae pv tomato DC3000 extracellular veicles in bacterial growth during plant infection.
Martin Janda, Christina Ludwig, Katarzyna Rybak, Chen Meng, Egidio Stigliano, Leon Botzenhardt, Beata Szulc, Jan Sklenar, Frank L.H. Menke, Jacob G. Malone, Andreas Brachmann, Andreas Klingl, and Silke Robatzek.
Vesiculation is a process employed by Gram-negative bacteria to release extracellular vesicles (EVs) into the environment. Bacterial EVs contain molecular cargo from the donor bacterium and play important roles in bacterial survival and growth. Here, we describe EV production in plant-pathogenic Pseudomonas syringae pv. tomato DC3000 (Pto DC3000), the causal agent of bacterial speck disease. Cultured Pto DC3000 exhibited EV structures both on the cell surface and in the vicinity of bacterial cells, observed as outer membrane vesicle (OMV) release. We used in-solution trypsin digestion coupled to mass spectrometry to identify 369 proteins enriched in EVs recovered from cultured Pto DC3000. The predicted localization profile of EV proteins supports the production of EVs also in the form of outer-inner-membrane vesicles (OIMVs). EV production varied slightly between bacterial lifestyles and also occurred in planta. The potential contribution of EVs to Pto DC3000 plant infection was assessed using plant treatments and bioinformatic analysis of the EV-enriched proteins. While these results identify immunogenic activities of the EVs, they also point at roles for EVs in bacterial defences and nutrient acquisition by Pto DC3000.
