The binding of Class II sRNA MgrR to two different sites on matchmaker protein Hfq enables efficient competition for Hfq and annealing to regulated mRNAs

The mutations introduced into eptB133 and ygdQ145 mRNA fragments. Nucleotide substitutions (indicated with arrows) were introduced into the AU-rich sequences (blue letters) of (A) eptB133 and (B) ygdQ145 mRNAs. The mutations introduced into eptB133_AU1_v1 and eptB133_AU2_v1 mutants are marked with black font, and substitutions in other mutants of eptB133 and ygdQ145 are marked with pink font. The single-stranded region deleted on the 5′ end of ygdQ145_AU1 is marked by a dashed line. The AUG start codons are boxed and SD sequences are marked in bold font.