Fig 4.

(A) Nucleotide sequence of the region encompassing the 3′ end of ureA and the 5′ end of ureB. The complete antisense sRNA, 5′ureB-sRNA (green line beneath the sequence), including the 5′ end (+1) and the putative −10 promoter sequence (red arrow) for 5′ureB-sRNA, is indicated. The nucleotides of loops of the stem-loop structures are highlighted (yellow for ureB mRNA and blue for 5′ureB-sRNA). (B) The putative stem-loop structures were generated using the RNAfold web server (http://www.tbi.univie.ac.at/). The complementary stem-loop structures (I-I*, II-II*, and III-III*) are shown. Position 1 in the sense RNA structure corresponds to nucleotide 151 of the ureB coding sequence (numbered on the right side of the sequence in panel A). A YUNR U-turn motif is indicated in stem-loop structures II and II*.