FIGURE 3.
Overproduction of FlaA does not improve motility. A, motility of various S. oneidensis strains. The wild type strain carrying pHG101-flaB (PflaB-flaB) was included (top) on the same soft agar plates in all motility analyses. Compared with the wild type with empty vector, overexpression of flaB resulted in increased motility as reported before (13). FFM (ΔflaAΔflaB) was used to evaluate impacts of overexpressed flaA driven by three different promoters. B, to determine the extent of FlaA overproduction in the strains from A, extracellular protein extracts were prepared from mid-exponential cells. Immunoblot analysis was performed to determine the levels of flagellin, and extracellular protein SO1072 was used as internal control. The antibody recognizes both FlaA and FlaB, and FFM is the flagellin-free mutant (ΔflaAΔflaB) used as a negative control.