FIG. 2.

Overproduction of S. aureus MurE enzyme in E. coli cells. Cells of BL21(DE3)/pLysS/pMuSa2 were grown and induced for 1 h with IPTG as described in the legend to Fig. 1. Cells were harvested at an OD of 0.8 and were disrupted by sonication. The protein contents from both soluble and membrane fractions obtained after high-speed centrifugation of the crude extracts were analyzed by SDS-PAGE. Molecular weight standards (in thousands) indicated on the left are as follows: phosphorylase b, 94; bovine serum albumin, 67; ovalbumin 43; carbonic anhydrase, 30; and soybean trypsin, 20. Lanes: A and B, analysis of the soluble fractions from noninduced and IPTG-induced cells, respectively; C and D, analysis of the membrane fractions from noninduced and IPTG-induced cells, respectively. The arrow points to the overproduced S. aureus MurE enzyme.