FIG. 2.

Subtilisin treatment of sheared bacteria infected with [³⁵S]methionine-[³⁵S]cysteine-labeled phages. Cultures of K17DE3/F⁺ and K17DE3tolA/F⁺ bacteria infected with [³⁵S]methionine-[³⁵S]cysteine-labeled phages were washed, sheared, divided in half, and then incubated in the presence (○) or absence (•) of subtilisin (Table 1, experiment 4) as described in Materials and Methods. Radiolabeled membranes (approximately 2 × 10⁵ cpm of K17DE3/F⁺ bacteria and 8 × 10³ cpm of K17DE3tolA/F⁺ bacteria) were analyzed as described in the legend to Fig. 1. Radioactivity, measured by counting 20 to 40% of each fraction for 10 min, is expressed as a percentage of the total in the gradient.