Fig. 3: T2SS Xps requirement for leaf tissue degradation and secretion of plant polymer-degradative enzymes.
a, Leaf discs of Col-0 and rbohD plants (5 weeks old) were mock treated (0.5× LB) or treated with cell-free supernatant (0.22 µm filter sterilized) of Xanthomonas Leaf131 or Leaf148 liquid cultures and incubated for 48 h. b, Genomic region of the T2SS operons xps and xcs in Xanthomonas Leaf131 and Leaf148. Letters indicate gene names and black line shows region of gene deletion. c,d, Leaf disc brightness was measured 24 h after inoculation with mock solution or with Xanthomonas wild-type or mutant strains of Leaf131 (c) or Leaf148 (d). Leaf discs were generated from Col-0 or rbohD plants (6 weeks old). Box plots show the median with upper and lower quartiles and whiskers present 1.5× interquartile range. Significant differences were calculated with ANOVA and two-sided Tukey’s honest significant difference post hoc test (n = 8, letters indicate significance groups, α = 0.05). e, Agar plates containing either skimmed milk, PGA, CMC, azo-xyloglucan or RBB-Xylan. Drops of 4 µl Xanthomonas Leaf131 wild-type or mutant suspension were pipetted onto agar plate. Pictures were taken 24 h after incubation at 22 °C. Quantification of halo diameter is shown in Supplementary Fig. 4. f, Leaf discs were treated with 0.22 µm filter-sterilized supernatant of liquid cultures from Xanthomonas Leaf131 or Leaf148 wild-type and xpsxcs mutants or mock solution (0.5× LB). Leaf discs were incubated for 48 h at 22 °C. AU, arbitrary unit; SN, supernatant; WT, wild type.
