Figure 2.

EMSA with cell extracts of wild-type (fis⁺) and fis⁻ strains. The 60-bp fragment (from positions −136 to −85) of P_mom (lane 1) was incubated with 5 nM Fis (lane 2), 1 µg of crude extract of E. coli MG1655 (lane 3), and 1, 5, 10 and 15 µg of crude extracts of E. coli BW25113 (lanes 4–7, respectively) and isogenic fis⁻ strain JW3229-1 (lanes 8–11, respectively). Specific shift as was observed with purified Fis could be seen with fis⁺ but not with fis⁻ extracts. Binding buffer for all reactions contained 400 mM NaCl.