Sequence difference between seven <i>rrn</i> operons.

<p>[A] Upper panel shows the 500 bp-long sequences upstream of the start site of mature 16S rRNA from all seven <i>rrn</i> operons. The sequences conserved between seven <i>rrn</i> operons are shown in black but the positions that differ from the conserved sequences are shown in white. Red bars indicated transcription start sites of upstream P1 and downstream P2 promoters. Marked variation was identified in the promoter regions, in particular, upstream from P1 promoter. [B] The positions of sequence variation within 16S and 23S rRNA are shown along the gene organization of <i>rrn</i> operons. A total of 33 and 77 differences were identified in 16S rRNA and 23S rRNA, respectively. [C] The number of bases that are different from the conserved sequence are shown for 16S and 23S rRNA for each <i>rrn</i> operon.