Fig. 2.

Motility and flagellar formation of the Pseudomonas chlororaphis wild type (O6), the gacS mutant (GacS-), and the complemented gacS mutant (ComGacS-) under swimming conditions. Data for an rpoS mutant (RpoS-) and its complemented mutant (ComRpoS-) also are shown in A and B. (A) The growth medium contained 0.3% agar to assay swimming motility. Data with standard deviations in parentheses are means of three independent experiments with at least five plates for each strain. (B) Number of polar flagella for cells isolated from 0.3% agar. (C) Images generated by transmission electron microscopy (TEM) of the P. chlororaphis O6 cells grown to stationary phase in 0.3% agar when swimming would be feasible. Data are means of three independent experiments with observations from 50 different colonies in each strain. Different letters indicate significant differences among P. chlororaphis O6 strains by Duncan’s multiple range test (P < 0.01).