FIG. 8.

Northern blot analysis of RNA transcripts from S. typhimurium ATCC 14028-1s and rpoS and ompR derivatives grown on LB medium plates without salt at 28 and 37°C. Probes covering the whole csgD and csgA genes were used; their locations are indicated in Fig. 4. Lanes: 1, UMR1; 2, MAE40 (rpoS); 3, MAE46 (ompR). The sizes of the bands detected by the respective probes are shown on the left, calculated by using a 0.24- to 9.5-kb RNA ladder (Life Technologies) as a standard. (A) Hybridization with the csgD probe; (B) hybridization with the csgA probe; (C) control hybridization with 16S RNA as described in Materials and Methods.