Figure 3.

Motilities of chimeras in Escherichia coli. Fresh colonies of RP6894 (E. coli ΔmotAB) were inoculated and incubated on 0.3% TB agar for 13 h (A) and 20 h (B) at 30°C. Each strain has the following plasmid: 1, vector plasmid pBAD33 (Vec); 2, pTF9 (PotB₅₉); 3, pTSK62 (PotB₉₁); 4, pTSK63 (PotB₁₂₉); 5, pTSK64 (PotB₁₃₈); 6, pHFAB (PomB). (C) Swimming speeds of the chimera strains of RP6894 were measured. After 6 h of culture in TG medium with 0.02% (w/v) arabinose, the cells were diluted 15-fold with TG medium. Swimming speeds were measured as described in Experimental Procedures. (D) Rotational switching of the flagellar motor observed by the tethered cell assay. “Switching fraction” means the proportion of the cell number of rotating cells who changed the direction at least one time in 30 sec against the total number of rotating cells.