FIG. 3.

Effect of sodium azide on the translocation of MerG. E. coli XL1-Blue carrying pMUE74 was cultured in Luria-Bertani medium and induced with 1 mM IPTG for 30 min. After a 2-h treatment with sodium azide, the cells were harvested and disrupted by boiling for 5 min, and the resultant supernatant was mixed with Ni-NTA resin (Qiagen) at room temperature for 16 h. After centrifugation, the pellet was washed, mixed with SDS-PAGE sample buffer containing 100 mM EDTA, and boiled for 5 min. The proteins in the sample were resolved by SDS-PAGE, and Coomassie brilliant blue was used for protein staining as described in Materials and Methods. p, the precursor MerG; m, the mature MerG. Mw, molecular mass markers (kilodaltons).