Figure 5.

The FtsH protease is involved in MgtC negative regulation mediated by MgtR. The thermosensitive E. coli ftsH mutant and the isogenic ftsH⁺ strain were transformed by plasmids pEG9094 (mgtC⁺) or pEG9091 del3 (mgtC⁺ mgtR⁺) (Figure 1A). Strains were cultured in low-Mg²⁺ medium for 36 h at 30°C or for 7 h at 30°C before an 18-h shift at 42°C. Total extracts were blotted with anti-MgtC antibodies or anti-DnaK antibodies.