Fig. 1: Dependence of E. coli colony expansion on initial glucose concentration.
Expansion dynamics of non-motile EQ59 E. coli colonies on 1.5 %(w/v) agar plates prepared with a defined concentration of glucose, 10 mM ammonium chloride, and 112 mM phosphate buffer at various times post-inoculation as a single cell. The seeding density of colonies is such that there are ~10 well-separated colony forming units (Fig. S1b) on a petri dish which is 60 mm diameter and has ~8 mm media depth with a total media volume of ~16 ml. The cross-sectional profile of colonies grown on a minimal media hard agar plate with 10 mM glucose (a), 20 mM glucose (b), and 30 mM glucose (c) as carbon source shown for various times (coded by color) post-inoculation. d–f The radius (μm) (d), height (μm) (e), and volume (μm3) (f) of the colonies plotted against the time (h) post-inoculation. Brown, cyan and black represent colonies grown on minimal media plates with 10 mM glucose, 20 mM glucose and 30 mM glucose respectively. In (d–f) each symbol shape represents an individual biological replicate. The observations reported in this figure on the effect of glucose concentration on colony expansion remains similar for colonies formed by a motile E. coli strain (Fig. S15).
