FIG 3.
Growth/survival of hvKP1 (wild type), hvKP1ΔiucA (aerobactin deficient), hvKP1ΔiroB (salmochelin deficient), hvKP1Δirp2 (yersiniabactin deficient), hvKP1ΔentB (enterobactin and salmochelin deficient), and hvKP1ΔentBΔirp2 (enterobactin, salmochelin, and yersiniabactin deficient) in human serum. The growth/survival of hvKP1, hvKP1ΔiucA, hvKP1ΔiroB, hvKP1Δirp2, hvKP1ΔentB, and hvKP1ΔentBΔirp2 was assessed by measurement of CFU at 0, 3, 6, and 24 h in 90% human serum–10% 1× PBS (pH 7.4). Data are means ± SEM; four independent growth curves were performed for each strain. The growth/survival of hvKP1ΔiucA was significantly decreased and the growth/survival of hvKP1ΔiroB, hvKP1Δirp2, and hvKP1ΔentB was significantly increased compared to that of hvKP1 (*, P < 0.05/5, two-tailed unpaired t test).