Fig. 3
From: Prokaryotic microvesicles Ortholog of eukaryotic extracellular vesicles in biomedical fields
Ultrastructural TEM images of cryo-sectioned Gram-negative cell envelopes. A: Cyanobacterium Phormidium uncinatum and B: Escherichia coli. Cyanobacterium Phormidium uncinatum has a combination of Gram-positive and –Negative structures. Note the thick peptidoglycan layer and outer membrane. The external layer (EL) consists of S- layer and oscillin fibrils with serrated surface morphologies (Scale bar: 100 nm). Reprinted adapted from [50]. (Copyright 2000, Journal of Bacteriology) [Cytoplasmic membrane: CM; outer membrane: OM; and Peptidoglycan: P]. Typical cell wall structure in Gram-negative (C) and Gram-positive bacteria (D)