FIG 3.

CL deficiency does not affect the PG composition of cells. (A) Quantification of muropeptides purified from R. sphaeroides wt cells, Δcls cells, wt cells treated with A22, wt cells treated with MEC, wt cells treated with FOS, and wt cells treated with DCS. A22 and MEC treatment decreased the relative abundance of muropeptide monomer by 33%, increased the relative abundance of crossed-linked muropeptides (dimer and trimer) by 20%, and increased the relative abundance of anhydrous muropeptides by 60%; all values are compared to wt cells. (B and C) These alterations in muropeptide composition yielded a PG with a higher level of cross-linking (B) and a shorter average strand length (C) than were seen with the wt cells. CL deficiency did not change the PG composition of R. sphaeroides Δcls cells, which resembled those of wt cells and wt cells treated with either FOS or DCS. Data represent mean values ± standard deviations obtained from three independent experiments. We used sub-MICs of the following inhibitors: A22 (10 μg/ml), MEC (0.5 μg/ml), FOS (250 μg/ml), and DCS (0.05 μg/ml).