Figure 35-6d: Introns, intein and possible splicesosome in the bnrd  region of SPbeta.  (A) bnrdE intron, (B) bnrdF intron, (C) BnrdE intein, and (D) possible intergenic splicesomal element.  Numbers indicate nucleotide position in SPbeta c2 prophage sequence (74), underlined sequences in (C) are conserved intein motifs (75), and double-underlined sequences are start/stop codons.