FIG 1.

A functional promoter dependent on a σ⁵⁴ factor is located upstream of sltF. (A) The 120-nucleotide sequence upstream of sltF is shown. The nucleotides shown in red correspond to the start and stop codons of sltF. The sequence similar to the σ⁵⁴ binding site is shown in boldface type. (B) Swimming plate for motility assays. The plate shows the swimming phenotype of wild-type WS8N, a sltF mutant strain (SltF), and the mutant strain complemented with two sltF constructs: SltF/pRKsltF, a construct with the gene coding for sltF and 120 bp upstream, and SltF/pRKrevsltF, a construct with the gene coding for sltF and 120 bp upstream cloned in the opposite sense of the vector promoter.