Figure 8.

An intragenic suppressor of benzamide dependence.

A. Suppressors of benzamide dependence. Strains 168 (WT), DWA454 (ftsZ sup9[FtsZ E251K]), DWA456 (ftsZ sup9^sup[FtsZ I228T, E251K]) and DWA33 (ftsZ cat[FtsZ I228T, E251K]) (SDM) were streaked on NA in the absence and presence of 8J (2 μg ml⁻¹), as indicated. Plates were photographed after incubation for 18 h at 37°C.

B and C. DWA456 divides in a benzamide‐independent manner. Exponentially growing cells of strain DWA456 were examined by microscopy following growth in the absence (B) and presence (C) of 8J (2 μg ml⁻¹). Arrowheads highlight unusual cell division events. Cell membranes were stained with FM5‐95. Scale bar = 5 μm.

D. I228V and I228L also provide benzamide independence. Strains DWA455 (ftsZ cat[FtsZ E251K]), DWA414 (ftsZ cat[FtsZ I228V, E251K]) and DWA419 (ftsZ cat[FtsZ I228L, E251K]) were streaked on NA + Cm in the absence and presence of 8J (2 μg ml⁻¹), as indicated. Plates were photographed after incubation for 18 h at 37°C.

E and F. Single mutants encoding I228L and I228V. Strains DWA401 (ftsZ cat[FtsZ I228L]) (E) and DWA402 (ftsZ cat[FtsZ I228V]) (F) were observed after growth overnight at 37°C on NA + Cm. Arrowheads in (F) highlight unusual cell division events. Scale bar = 5 μm.