Figure 1. Morphological features of L. monocytogenes L-forms.

(A) The size distribution of L-forms (n = 2801) (squares) and its subpopulation containing intracellular vesicles (n = 211) (circles) is represented as the relative frequency per 1 µm size classes. Cells from the whole population have an average diameter of 6.1±3.1 µm. L-forms containing intracellular vesicles have an average diameter of 9.4±4.4 μm. (B) The subpopulation with intracellular vesicles was divided in a group with 1, 2 or 3 intracellular vesicles (squares) and a group with 4 or more intracellular vesicles (circles). Cumulative frequency curves are shown for both groups in incremental steps of 1 µm. Four or more intracellular vesicles have been mainly accumulated by the larger L-form cells.