Table 1.
Burkholderia cepacia complex used in this work and VR relative to the different killing assays.
Fig 1.
Kaplan-Meier survival plots for L4 N2 worms fed with exemplifying Bcc strains for different VR grown on PGS medium.
Worms fed on: B. metallica (VR 3; black line; n = 113; 0% survival at day 2); B. seminalis (VR 2; blue line; n = 150; 34% survival at day 2); B. dolosa (VR 1; redline; n = 198; 69% survival at day 2); B. multivorans (VR 0; green line; n = 120; 93% survival worms). n: Number of worms at day 0. All p-values, comparing each survival curve between them, resulted to be < 0.0001, calculated with "Log-rank (Mantel-Cox) Test" with the Graph-pad Prism 5 software.
Fig 2.
Kaplan-Meier survival plots for L4 stage WT worms fed with: E. coli OP50 (solid lines), Bcc strains on NGM (dashed lines), Bcc strains on PGS (dotted lines). n: Number of worms at day 0.
A) The pathogenicity of Bcc strain B. cepacia on SKA (n = 93) was compared with the ability on FKA (n = 184). B) The pathogenicity of Bcc strain B. metallica on SKA (n = 80) was compared with the ability on FKA (n = 113). C) The pathogenicity of Bcc strain B. stabilis on SKA (n = 87) was compared with the ability on FKA (n = 161). P-values were calculated between survival curves on FKA and SKA of each bacteria, and resulted to be < 0.0001 calculated with "Log-rank (Mantel-Cox) Test" with the Graph-pad Prism 5 software.
Fig 3.
The ability of Bcc strains to accumulate in C. elegans intestinal lumen was evaluated with microscopy analysis.
Red arrows indicate the nematodes intestine. A) Intestinal lumen of one L4 stage WT worm after 4 h of incubation on NGM plate spotted with E. coli OP50, and B) after 24 h of incubation on the same plate. C) Intestinal lumen of one L4 WT after 4 h of incubation on NGM plate spotted with B. pseudomultivorans (VR 0 on SKA, and D) after 24 h of incubation on the same plate. E) Intestinal lumen of one L4 WT after 4 h of incubation on NGM plate spotted with B. metallica (VR 3 on SKA, and F) after 24 h of incubation on the same plate.
Fig 4.
Secreted compounds or toxins mediate fast killing.
Data reports paralysis and mortality at 4 and 24 h of worms plated on PGS medium plates treated with Bcc strains or E. coli grown on a sterile disk. Data represent mean values of three independent experiments and SD values are reported. P-values were calculated between sample (Bcc) and control (OP50) at the corresponding time, and were always < 0.05.
Table 2.
MRP knock-out C. elegans mutants mortality expressed as percentage of dead worms and comparison between the mutants and the WT.
Mutant mrp-5 was tested as heterozygote, due to lethality of the mutation in homozygosis. Statistical significant differences appear highlighted, with negative values indicating statistically significant reductions in mortality from WT, and with positive values indicating statistically significant increases in mortality from WT.
Fig 5.
Ward’s method with a consistency threshold 1.1 used to cluster mutants based on significant changes in pathogenicity.
Table 3.
Effect of ABC inhibitors during C. elegans- Bcc infection on SKA.
Nematodes mortality expressed as percentage of dead worms and compared between samples with inhibitors and control with DMSO (0,5%). Statistical significant differences were reported.