Bacterial Strains, Plasmids, and Growth Conditions. The Escherichia coli JM109 High Efficiency Competent Cells (Promega) used for cloning procedures were grown in Luria-Bertani (LB) medium
supplemented with ampicillin (50 lg mL)1) when required. Plasmid DNA was purified with Wizard Plus SV Minipreps (Promega) and DNA sequencing was performed on both strands with universal
primers (T7 and SP6) by a commercial facility (MWG Biotech,Germany). The plasmid pGEM-T easy vector (Promega) was used as a general vector for cloning and sequencing.