Fig. 6. Stopped-flow analysis of SPM-1 catalysed meropenem hydrolysis. (A) Apo-SPM-1 (100 μM) was incubated with Zn(ii) (200 μM) for ∼10 min then mixed with meropenem (100 μM) (5 °C); (B) apo-SPM-1 (100 μM) was incubated with Co(ii) (500 μM) for ∼10 min, then mixed with meropenem (100 μM); (C) global fit traces and proposed kinetic mechanism. Global fit traces and proposed kinetic mechanism (assuming that only di-Co(ii) substituted SPM-1 (E) is present in solution before the reaction due to 5-fold excess of Co(ii) used for the experiment).