FIG 3.

Expression of the UDP-GlcNAc 2-epimerases is required for B. anthracis vegetative growth. B. anthracis Sterne(pJK4) and YW6(pJK4) were cultured overnight in BHI with 20 μg ml⁻¹ kanamycin and 1 mM IPTG. Bacteria were centrifuged, washed, and suspended in fresh medium either without (−IPTG) or with (+IPTG) 1 mM IPTG supplement and incubated at 37°C. At timed intervals (1 to 10 h), culture aliquots were withdrawn, samples were fixed with glutaraldehyde, and phase-contrast microscopy images of bacteria were acquired at an ×400 or ×1,000 magnification. Bar, 20 μm. Data are representative of three independent experimental determinations.