The Impact of the CpxA on Regulating Polymyxin B Resistance in Salmonella Typhimurium

Polymyxin B is considered as a last-resort antibiotic for multidrug-resistant or extensively drug-resistant gram-negative bacterial infections. Addressing Salmonella resistance to polymyxin B is crucial for global public health. Our study revealed that CpxA/ArcB knockout inhibits the motility, tolerance to acid stress and oxidative stress of S.typhimurium. Most notably, the tolerance of S.typhimurium to polymyxin B could be increased by either CpxA or CpxA/ArcB deletion. In this study, transcriptomic detection and analysis were used to clarify the mechanisms by which CpxA-deleted S.typhimurium is involved in resistance to polymyxin B stress, which may be related to processes such as increased assembly of bacterial flagella.