Fig. 1. Scanning electron micrographs showing B. thetaiotaomicron ATCC 29741 just before and after extraction. After collection from agar medium the bacteria were suspended in
the extraction solution; bacilli with dense content and a fringed surface can be observed (aec). After extraction for 20 h in the solution bacteria are producing buds or vesicles with a
dense content (def). Arrows pointing at portions of the bacterium surface showing initiation (e) and the subsequent vesicle formation (f). Scale bars, 500 nm (a) 100 nm (bef).