FIG 2.

Survival as a function of the rate of medium exchange. Strains Frag1 (wild type), MJF367 (ΔmscL), MJF451 (ΔmscS), MJF429 (ΔmscS ΔmscK), MJF465 (ΔmscL ΔmscS ΔmscK), MJF612 (ΔmscL ΔmscS ΔmscK ΔybdG), and MJF641 (with all seven mechanosensitive channels knocked out) were exposed to a 0.5 M NaCl shock performed at various rates of medium exchange. The survival depends on the rate of the osmotic challenge as well as on the type of MS channels present. The solid lines represent a fit to the initial linear region of the survival response curves. The dashed lines at 90% and 50% represent reference lines for wild-type-like survival and an arbitrary survival percentage used for strain comparison, respectively. The medium exchange rates where survival is ∼50% for the various strains are listed to the right to provide a gauge of rate sensitivity. For further details, see Materials and Methods.