The reaction mixtures comprised 50 ng of recom binant MurE enzyme purified as described previously with
25 mM Bis–Tris–propane/HCl (pH 8.5), 5 mM MgCl2, 50 M ATP, 50 M UDP-MurNAc-l-Ala-d-Glu and 4% v/v) dimethyl sulphox ide (DMSO) (enzyme reaction) at 37 ◦C.