FIG. 3.

Expression in E. coli BL21 λDE3 of gafD constructs. (A) Schematic presentation of GafD and the truncated GafD peptides and their recovery from the periplasm by affinity chromatography. Black arrow, position of the cleavage site in ΔGafD; ΔGT, position of the in-frame deletion abolishing binding activity. (B) Autoradiographic analysis of pulse-labeled peptides in the whole cells (C; lanes 1, 4, 7, and 10), spheroplasts (S; lanes 2, 5, 8, and 11), and the periplasm (P; lanes 3, 6, 9, and 12) of E. coli BL21 λDE3 expressing gafD constructs. The DNA fragments encoded full-length GafD1-321 (lanes 1 through 3) and the truncated forms GafD1-157 (lanes 4 through 6), GafD1-252 (lanes 7 through 9), and GafD1-178 (lanes 10 through 12). The migration distances of molecular weight markers are indicated on the left; those of the GafD and the ΔGafD peptides are indicated on the right. Open arrow, migration distance of β-lactamase.