Figure 2.

Characterization of T. denticola wild-type, ΔflgE, ΔmotB. (A) Growth of T. denticola wild-type and mutants. T. denticola cultures at stationary phase were inoculated into fresh OBGM medium at t = 0. A₆₅₀ of the cultures was measured at 6–24 h intervals for 264 h. The mean generation time was calculated based on the rate of change of A₆₅₀ during the exponential growth phase of cultures (N = 3). The mean generation times were statistically analyzed using a one way ANOVA with both mutants ΔmotB and ΔflgE significantly different (p < 0.05) to WT. (B) Colony morphologies of T. denticola wild-type and ΔmotB. T. denticola cells were inoculated into OBGM agar [0.8% (w/v) agarose] and poured into petri dishes which were then incubated anaerobically for 2 weeks. The colonies formed by ΔflgE had a similar morphology to the colonies of ΔmotB. (C) Swimming assay of T. denticola wild-type and mutants. T. denticola cells harvested at exponential phase were spotted on semisolid OBGM agar [0.4% (w/v) agarose and 1% (w/v) gelatin] and incubated anaerobically for 10 days before the area of turbid plaque was measured. The data are presented as means plus standard deviations (N = 29) and were analyzed by Students' T-test. Values that were significantly different (p < 0.05) from the value for T. denticola wild-type are indicated by an asterisk (^*). A representative image of the swimming assays of T. denticola wild-type, ΔflgE, ΔmotB after 10 days of anaerobic incubation is shown. (D) Autoaggregation of P. gingivalis W50, T. denticola wild-type and mutants. T. denticola and P. gingivalis cells harvested at exponential phase were washed twice with coaggregation buffer and adjusted to A₆₅₀ of 0.5. The height of bacterial aggregates was monitored for 7 h. The data are presented as means and standard deviations (N = 3).