FIG. 2.

Effects of mlc, nagC, and nagA mutations on growth rates on GlcN. Bacteria were grown in minimal MOPS medium with 0.2% GlcN as described in Materials and Methods. (A) Wild-type NagB⁺; (B) Phe174Ala mutant; (C) Tyr121Ser mutant. Representative growth curves for the nagB strains and their mlc, nagC, and nagA versions are shown. The Phe174Ala mutant did not grow on GlcN in the absence of a nagC or nagA mutation. The slowly growing Tyr121Ser and Tyr121Ser mlc strains were stored overnight at 4°C and then rediluted to an A₆₅₀ of 0.05 and regrown the next day. wt, wild type.