FIG. 3.

Serum sensitivities of wzz mutants. Bacteria were incubated for 1 hour at 37°C with shaking in either 12.5% or 20% human serum. Neither PBS nor heat-inactivated serum had an effect on bacterial viability. Percent survival was calculated as follows: [(number of bacteria recovered)/(number of bacteria added)] × 100. Bars represent the means of at least three experiments, and error bars represent the standard deviations. One-way analysis of variance (Kruskal-Wallis test) of the 12.5% serum concentration results showed statistically significant differences between groups (P < 0.05). *, statistically significant difference (P < 0.05) compared to wzz2 as determined with the Mann-Whitney U test. No statistical significance was determined by either one-way analysis of variance or t tests for the 20% serum data sets. DM, double mutant.