FIG. 2.

Sequence comparison of response regulator promoter regions from H. pylori strains 26695, J99, and Afr7. Matched shadings denote sequence similarities of predicted coding regions, and patterned regions illustrate extragenic sequence homology. Asterisks indicate unsequenced regions where nucleotide homology is unknown. Black arrows indicate transcription start points for the response regulator (RR)-histidine kinase (HK) operon that was previously determined in H. pylori strain 26695 (10, 17). Predicted transcription start points in H. pylori strains Afr7 and J99 are based upon sequence homology with the orthologous region in strain 26695. White half-arrows represent binding sites for primers insFwd and insRev. The amplicon without ins180 is 350 bp, and amplicons with ins180 and ins480 are ∼530 and ∼830 bp long, respectively.