Fig. 2

Effect of nitric oxide production on EHEC’s colony-forming capacity. EHEC O157 Sakai wild-type (WT) or the narGHJI deletion mutant (ΔnarGHJI) were grown for 3 h at 37 °C in LB pretreated with (100 μM) or without (0) NOR-4 and used to infect HeLa cells for 5 h, including 3.5 h post-washing. a. Growth of EHEC strains in the presence/absence of NOR-4. The representative of three independent experiments is shown. b. Effect of NOR-4-containing medium on the colony-forming capacity. Microcolonies were visualized by staining with Giemsa. The average of three independent experiments along with the standard error is shown. *: p < 0.05, ns: not significant