Figure 3.—

Phenotypic tests of MalT activity. The ancestral strain is labeled 606. One evolved clone was isolated at 20,000 generations from each of the 12 populations designated Ara − 1–Ara-6 and Ara + 1–Ara + 6. A malT-deleted strain (ΔmalT) served as a control. (A) Growth ability in DM250 maltose at 37°. +, Growth after 8 hr; −, no growth even after 24 hr. (B) Relative level of LamB protein. Cellular extracts were prepared from all strains after overnight culture in DM250 medium. Each sample contained 20 μg of total protein and was subjected to 12% SDS–PAGE and immunoblot analysis with polyclonal antibodies against LamB (anti-LamB) or RpoA (anti-RpoA) as a control. (C) The number of mutations identified in malT in each population is indicated. Δ, deletion allele; Anc, ancestral state.