Figure 1. Hsp90_Ec overproduction leads to decreased cell survival, filamentation and SDS sensitivity in E. coli.

(A) E. coli MG1655 cells harboring the Hsp90_Ec overexpression plasmid (pHsp90_Ec) or vector were grown at 37°C in the presence of 0.2% arabinose to induce Hsp90_Ec production. The number of viable cells was determined as described in Supplemental Information and plotted as colony forming units (CFU) per mL.

(B) Cells described in (A) were incubated at 37°C in the presence of 0.2% arabinose and growth was followed by measuring OD₆₀₀.

(C–D) Cells expressing Hsp90_Ec from pHsp90_Ec (C) or carrying the empty vector

(D) were grown overnight at 37°C in the presence of 0.2% arabinose and visualized by DIC microscopy. Size bars are 10 μm.

(E) Cells expressing Hsp90_Ec from pHsp90_Ec or carrying the empty vector were grown without arabinose to early stationary phase and aliquots of 10-fold serial dilutions were spotted on LB-ampicillin plates (Amp) containing 0.2% arabinose (Ara) and 1% SDS as indicated. Plates were incubated overnight at 37°C.

In (A) and (B), data from three replicates are presented as mean ± SEM.

See also Figure S1.