Fig 1.

Analysis of the intergenic region between the genes iga and trpB. (A) Schematic of iga-trpB locus in gonococci and meningococci. The 1,134-bp region of genomic DNA from N. gonorrhoeae strain MS11 that was cloned into the complementation constructs is also represented. The transcriptional terminator shared by iga and trpB is indicated by a stem-loop structure. Meningococcal strains contain a 103-bp Correia element (black rectangle) inserted between the stop codon of trpB and the transcriptional terminator. (B) Changes made to the iga-trpB intergenic region in the complementation constructs. The stop codons of trpB and iga are underlined. A second transcriptional terminator from the erythromycin resistance gene ermC was inserted downstream of iga, and a restriction site was added between the two terminators for cloning purposes (bold type). All gene insertion is directed into this restriction site, such that both iga and trpB maintain transcriptional terminators.