Changes in Brassica oleracea Leaves Infected With Xanthomonas campestris pv. campestris by Proteomics Analysis

Understanding plant's response mechanisms against pathogenesis is fundamental for the development of resistant crop varieties and more productive agriculture. In this regard, "omic" approaches are heralded as valuable technologies. In this work, combining isobaric tags for relative and absolute quantification (iTRAQ) technology with mass spectrometry, the proteomes from leaves of Brassica oleracea plants infected with Xanthomonas campestris pv. campestris (Xcc), and control plants at two different post-infection times were compared. Stronger proteomic changes were obtained at 12 days post-infection in comparison with 3 days. The responses observed involved different cell processes, from primary metabolism, such as photosynthesis or photorespiration, to other complex processes such as redox homeostasis, hormone signaling, or defense mechanisms. Most of the proteins decreased in the earlier response were involved in energetic metabolism, whereas later response was characterized by a recovery of primary metabolism. Furthermore, our results indicated that proteolysis machinery and reactive oxygen species (ROS) homeostasis could be key processes during this plant-pathogen interaction. Current data provide new insights into molecular mechanisms that may be involved in defense responses of B. oleracea to Xcc.