FIG. 6.

X. campestris pv. campestris nagA mutants are sensitive to N-acetylglucosamine. (A) Effect of addition of N-acetylglucosamine (GlcNAc) on growth of the ΔnagA mutant cultivated in minimal medium containing various carbon sources at a concentration of 20 mM. After 3 h of growth, media were supplemented (+) or not supplemented (−) with N-acetylglucosamine at a concentration of 10 mM. The error bars indicate the standard deviations obtained from 4 independent experiments. (B) Effects of different concentrations of N-acetylglucosamine (GlcNAc) on growth of nagA::pVO (dashed lines) and ΔnagA (solid lines) mutants. Cells were grown in minimal medium containing the concentrations of GlcNAc indicated. The error bars indicate the standard deviations obtained from 4 independent experiments. (C) Effects of secondary mutations on the GlcNAc sensitivity of the ΔnagA mutant. Strains were streaked on complete medium plates containing 10 mM N-acetylglucosamine (upper plate) or 10 mM xylose (lower plate). Region 1, wild-type strain; region 2, ΔnagA mutant; region 3, ΔnagP mutant; region 4, ΔnagP ΔnagA mutant; region 5, ΔnagK-IIAB mutant; region 6, ΔnagK-IIAB ΔnagA mutant. The photograph was taken after 96 h of growth. Identical results were obtained on minimal medium plates.