FIGURE 2: Pulse-chase analyses in wild-type and formylation-lacking fmt E. coli in the absence or presence of actinonin, an inhibitor of deformylation.

(A) Wild‑type E. coli were pulse-labeled with ³⁵S-methionine/cysteine for 1 min, followed by a chase (in the presence of chloramphenicol, a translation inhibitor) for indicated times, extraction of proteins, SDS-PAGE, and autoradiography. Pulse-chases were carried out either in the absence of actinonin (lanes 1-3) or in the presence of increasing concentrations of actinonin (lanes 4-12). Molecular masses of protein markers are indicated on the left.

(B) Same as in (A) but pulse‑chases were carried out in the absence of chloramphenicol in wild-type cells (lanes 1-9) and congenic fmt E. coli (lanes 10-18).