FIG 2.
Filament morphology and swim phenotype of multiple-deletion flaA flagellin mutants. (A) All ΔflaA mutants exhibit straight filaments, and the ΔflaABCD mutant is aflagellate. The left column shows multiple filaments per mutant (indicated by arrows), and the right column shows zoomed-in images of 1 or 2 filaments. Images were captured at magnifications of ×6,000 (left) and ×60,000 (right). The ΔflaABCD mutants are aflagellate and show hooks. The scale bar of 1 μm applies to all images on the left, and the scale bar of 100 nm applies to all images on the right. (B) Swimming motility phenotype of all ΔflaA mutants harboring plasmid-borne flaA. Shown are swim ring diameter data (7-day incubation) for complementation of all ΔflaA mutants with plasmid-borne expression of flaA expressed (Plac-PflaA-flaA). Data are normalized to the wild type. White bars are the wild type or original mutants, and the black bars are wild type or the mutants carrying Plac-PflaA-flaA. Values are the averages for three swim plates per strain.