Cultivation and Reagents for Pathogenic Bacteria

Phytopathogenic Xanthomonas spp. were cultivated in nutrient agar (NA) at 28 °C^{59 (link)}, and E. coli strains DH5α and BL21(DE3) were cultured in Luria Bertani (LB)⁶⁰ medium at 37 °C. Tryptic soy broth (TSB; 30 g/L) was used for culturing Pseudomonas strains at 30 °C. The fungus M. oryzae R01-1 was grown in oatmeal (OAM)⁶¹ medium at 25 ˚C. The strains, plasmids and primers used in this study are listed in Supplementary data 1 and 2. When required, antibiotics were added at the following final concentrations (µg mL⁻¹): kanamycin (Km), 25; rifampicin (Rif), 75; gentamicin (Gm), 20; and spectinomycin (Sp), 25. Chemical reagents including petroleum ether, ethyl acetate, n-butyl alcohol and methanol were purchased from Macklin (Shanghai, China). Phenazine-1-carboxylic acid (PCA) was provided by Dr. Yawen He (School of Life Sciences and Biotechnology, Shang Hai Jiao Tong University). Restriction enzymes were purchased from Takara Bio (Europe AB).