We analyzed cellular proteome of mycelium of Verticillium albo-atrum. A reference map of cellular proteins was established and samples from two fungal pathotypes from hop were compared. We found many differences between the two pathotypes including both proteins detected specifically in only one of the two pathotypes and proteins with significantly different abundance between pathotypes. We identified 50 differentially expressed proteins, which functionally belonged mostly to proteins of oxidative stress, cytoskeletal proteins and enzymes of protein and energy metabolism.
We cultured six isolates, belonging to mild and lethal pathotypes and originating from three countries, in a simulated xylem medium to mimic in vivo nutritional conditions and therefore induce the secretion of proteins that are relevant to plant-pathogen interaction. Secretome samples were analyzed by two-dimensional difference gel electrophoresis (2D-DIGE), followed by protein identification with MALDI-TOF/TOF mass spectrometry. Comparison of mild and lethal isolate from the same country revealed the most differences between German isolates, followed by Slovenian and English isolates. We identified over 180 protein spots with identified proteins mostly belonging to different cell wall-degrading enzymes, proteases, esterases, oxidoreductases and fungal cell wall proteins.