Figure 7: Lys is involved in stress-induced MV formation of planktonic cells.
From: Explosive cell lysis as a mechanism for the biogenesis of bacterial membrane vesicles and biofilms
(a) MV production in P. aeruginosa PAO1 and isogenic mutants were analysed after 16 h of incubation under oxic planktonic growth conditions. n=3; mean±s.d. (b) MV production in P. aeruginosa PAO1 and isogenic mutants were analysed after 16 h of incubation under anoxic planktonic growth conditions. Values indicate the mean±s.d. of three replicates. n=3; mean±s.d. #P<0.001 versus wild type (WT) (Student’s t-test). (c) MV production by planktonic P. aeruginosa PAO1 and isogenic mutants cultured in the presence of MMC (200ngmL−1) relative to no MMC, n=3; mean±s.d. #P<0.0005 (Student’s t-test). (d) Catalytic activity of Lys is required for genotoxic stress-induced MV formation, n=3; mean±s.d. #P<0.0005 (Student’s t test). (e) MA plot showing the comparison of mRNA levels associated with MVs with the transcript levels of stationary phase cells. More and less abundant transcripts in MVs are indicated by red and green dots, respectively (P value <0.02). Transcripts from the pyocin gene cluster (PA0610 to PA0648) are circled in black. (f) Promoter activities of recA, hol and lacZ (control) under non-inducing conditions were monitored by the aid of plasmids containing transcriptional fusions of the respective promoter regions to eGFP. Cells expressing GFP are green; scale bar, 2.5 μm.
