Deciphering the functions of type II and type IV secretion systems from the plant-pathogenic bacterium Xanthomonas campestris pv. vesicatoria
Final Report Abstract
The Gram-negative plant-pathogenic bacterium Xanthomonas euvesicatoria is the causal agent of bacterial spot disease on pepper and tomato plants and is one of the model organisms to study the secretion of bacterial virulence factors. Focus of the present project was the analysis of type II secretion (T2S) and type IV secretion (T4S) systems and their contribution to virulence and protein secretion. We previously reported that the Xps-T2S system secretes degradative enzymes and is highly specific for substrates of X. euvesicatoria. Substrate recognition presumably depends on a periplasmic assembly platform which is connected to the secretin channel in the outer membrane. In the previous funding period, we generated a modular T2S system by Golden Gate cloning, which allows the rapid deletion or insertion of genes and thus facilitates the functional characterization of T2S system components. Mutant and protein interaction studies revealed the presence of an XpsCLM assembly platform complex which is essential for T2S but dispensable for secretin formation. We also optimized in vitro T2S conditions and identified novel T2S substrates by mass spectrometry analysis of apoplastic fluid from infected plant tissue. In addition to the T2S system, we studied the function of the VirB/VirD4 and the Icm/Dot T4S system from X. euvesicatoria. We showed that T4S genes are expressed and encode components of oligomeric complexes corresponding to known assemblies of VirB/VirD4 and Icm/Dot proteins. Extensive infection assays revealed that virB/virD4 and icm/dot genes are dispensable for virulence, however, both T4S systems secrete the relaxase TraI, which presumably mediates plasmid transfer. Conjugation experiments confirmed that the VirB/VirD4 T4S system transfers a natural plasmid between different X. euvesicatoria strains.
Publications
-
Functional characterization of the Xcs and Xps type II secretion systems from the plant pathogenic bacterium Xanthomonas campestris pv vesicatoria. New Phytologist, 187(4), 983-1002.
Szczesny, Robert; Jordan, Matthias; Schramm, Claudia; Schulz, Steve; Cogez, Virginie; Bonas, Ulla & Büttner, Daniela
-
The xylan utilization system of the plant pathogen Xanthomonas campestris pv campestris controls epiphytic life and reveals common features with oligotrophic bacteria and animal gut symbionts. New Phytologist, 198(3), 899-915.
Déjean, Guillaume; Blanvillain‐Baufumé, Servane; Boulanger, Alice; Darrasse, Armelle; de Bernonville, Thomas Dugé; Girard, Anne‐Laure; Carrére, Sébastien; Jamet, Stevie; Zischek, Claudine; Lautier, Martine; Solé, Magali; Büttner, Daniela; Jacques, Marie‐Agnès; Lauber, Emmanuelle & Arlat, Matthieu
-
Xanthomonas campestris pv. vesicatoria Secretes Proteases and Xylanases via the Xps Type II Secretion System and Outer Membrane Vesicles. Journal of Bacteriology, 197(17), 2879-2893.
Solé, Magali; Scheibner, Felix; Hoffmeister, Anne-Katrin; Hartmann, Nadine; Hause, Gerd; Rother, Annekatrin; Jordan, Michael; Lautier, Martine; Arlat, Matthieu & Büttner, Daniela
-
Functional characterization of VirB/VirD4 and Icm/Dot type IV secretion systems from the plant-pathogenic bacterium Xanthomonas euvesicatoria. Frontiers in Cellular and Infection Microbiology, 13.
Drehkopf, Sabine; Scheibner, Felix & Büttner, Daniela
-
Poster presentation (FEMS meeting, July 2023): (Poster) Functional characterization of VirB- and Icm/Dot-like type IV secretion systems from the plant-pathogenic bacterium Xanthomonas euvesicatoria
Drehkopf S. & Büttner D.
