Skip to main content
. Author manuscript; available in PMC: 2015 Jul 1.
Published in final edited form as: Mol Microbiol. 2014 Jun 4;93(1):183–198. doi: 10.1111/mmi.12650

Figure 2. Vesicles are produced directly by the cell not by aggregation of lipids.

Figure 2

Strain 168 cells were grown in the presence of GXM and vesicles were isolated and left natural or sonicated. (A) Schema of experimental design. Vesicles were predicted to either (i) be gold-free if they were formed by cellular processes at the cell membrane or (ii) encapsulate gold particles if they formed in the presence of GXM (e.g. spontaneous formation in supernatant containing GXM). Immunogold was used to delineate the presence of GXM in individual vesicles at ultrastructural scales. In the schema, black dots represent gold particles and red lines, GXM. (B) Representative micrograph showing immunogold staining of GXM in a vesicle preparation. Note that all gold particles occur outside of vesicles. (C) Percentage of natural and sonication-derived vesicles in the presence of GXM that contained gold particles. Sonicated vesicles contained significantly more gold than natural vesicles (4.8 and 1.8%, n=564 and n=712, p<0.01 Chi2) and demonstrated a significantly smaller (D) diameter and standard deviation (94.54 ± 1.869, n=392 and 115.4 ± 2.69, n=355, p<0.0001 unpaired t-test, n=3) than natural vesicles. Black arrows indicate vesicles and white arrow indicates GXM. Scale bars 100 nm.