Figure 3.

In vitro characterization of LdtA. Muropeptides were identified and quantified using HPLC; no reaction products other than those shown in the figures were detected. (A) The percentage of substrate converted into product via in vitro L,D-transpeptidation by LdtA is shown for various muropeptides. Reactions were incubated for 30 min (purified muropeptides) or 2 h (sacculi). (B) The percentage of mono4 altered by in vitro LdtA transpeptidation to have a different terminal amino acid when incubated (2 h) in the presence of the indicated L- or D-amino acid is shown. The data shown in (A) and (B) are representative of three and two independent experiments, respectively.