FIG 3.

P. aeruginosa PAO9503 OMVs produced during biofilm growth are smaller than planktonic-derived P. aeruginosa PAO9503 OMVs. (A and B) Transmission electron micrographs of PAO9503 pBBR1MCS-5 planktonic derived OMVs (A) and PAO9503 pBBR1MCS-5 biofilm derived OMVs (B). Scale bar, 500 nm. Images are representative of n = 3 biological replicates. Arrows indicate OMVs. (C and D) ZetaView NTA of OMVs isolated from PAO9503 pBBR1MCS-5 planktonic (C) or biofilm (D) cultures. Data shown are means + SEM of n = 5 biological replicates. (E) The size range of P. aeruginosa PAO9503 planktonic derived OMVs (pOMVs, circles) and biofilm derived OMVs (bOMVs, squares), represented as a percentage of the total OMV population. pOMVs are represented by circles (dark gray bars), and bOMVs are represented by squares (light gray bars). Data are presented as means ± SEM of n = 5 biological replicates. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ns, not significant (Student's t test). (F) The number of P. aeruginosa PAO9503 pOMVs (circles, dark gray bar) and bOMVs (squares, light gray bar) per 10⁸ bacteria in individual cultures at the time OMVs were collected was determined by NTA. Data are means ± SEM of n = 4 biological replicates. ns, not significant (Student's t test).