"Black rot" is caused by the pathogenic bacterium Xanthomonas campestris pathovar campestris (or Xcc). Under favorable conditions (high humidity and temperature), Xcc infects vegetable crops by spreading through the plants' vascular tissues, turning the veins in their leaves yellow and black, and causing V-shaped lesions along the margins of the leaves. All vegetables in the crucifer family, including broccoli, Brussels sprouts, cabbage, cauliflower, kale, mustard, radish, rutabaga, and turnip, are potential hosts for Xcc. The model plant Arabidopsis thaliana is also susceptible to Xcc infection. Surprisingly, however, some wild cruciferous weed species do not manifest the characteristic symptoms of "black rot" disease when infected.
To date, there is no effective treatment for Xcc infection, so in hopes of developing a treatment, scientists at four Chinese institutions (the Institute of Microbiology at the Chinese Academy of Sciences, the Chinese National Human Genome Center at Shanghai, Guangxi University, and the Chinese National Human Genome Center at Beijing) have focused their efforts on characterizing the genes responsible for Xcc pathogenicity. In their study published today, the investigators describe the identification of 75 different genes responsible for Xcc virulence. These genes appear to belong to 13 different functional categories or related metabolic pathways. The researchers hope that the molecular characterization of these pathogenicity-related genes will lead to the development of a treatment
Contact: Maria A. Smit
Cold Spring Harbor Laboratory