FIG. 1.

Identification of sseL, a new member of the SsrB regulon. (A) Relative expression ratios of sseL between wild-type Salmonella, an ssrB mutant, and a ydgT mutant (11). Green indicates a negative relative expression in the ssrB mutant compared to wild type, and red indicates a positive relative expression in ydgT mutants compared to the ΔssrB strain. (B) Expression of SseL requires SsrB. Wild-type and ssrB mutant Salmonella strains expressing an SseL-HA fusion protein were grown in SPI2-inducing medium. Whole-bacterial-cell lysates were examined by Western blotting for the expression of each protein. As controls, bacterial lysates were probed for the SsrB-dependent protein, SseB, and the SsrB-independent protein, DnaK. (C) The syntenic gene environment surrounding sseL in S. enterica serotype Typhimurium (top) was compared to the assembled, preannotated S. bongori genome downloaded from the Wellcome Trust Sanger Institute (bottom). Vertical green and yellow lines represent regions of sequence identity between the two genomes, and the absence of vertical lines indicates divergence or absence of the corresponding sequence in the S. bongori genome. Number ranges following the species name indicate the nucleotide positions of the genome region within the aligned window.