Mutations at four distinct regions of the rpoB gene can reduce the susceptibility of Helicobacter pylori to rifamycins.

The transformation of a panel of rpoB mutations (codons 525 to 586) from rifampin-resistant donor strains into Helicobacter pylori 2802A confirmed the MICs associated with the respective mutations. RpoB V149X random mutations were generated and induced different levels of resistance, depending on the replacement amino acid. Mutagenesis of the rpoB gene at codon position 701 (R701H) induced low-level resistance.