DNA-binding dual transcriptional regulator OmpR (OmpR)

The DNA-binding dual transcriptional regulator OmpR is a cytoplasmic response regulator that belongs to the EnvZ/OmpR two-component system, a ubiquitous signaling mechanism in Gram-negative bacteria. It plays a pivotal role in bacterial adaptation to environmental changes, particularly osmotic and acid stress, by differentially regulating the expression of outer membrane porins like OmpC and OmpF. Beyond its classical role in osmoregulation, OmpR acts as a global regulator of virulence factors, including those involved in motility, biofilm formation, and host-cell adhesion. This regulatory profile makes it an attractive therapeutic target for anti-virulence strategies intended to disarm pathogens without imposing the heavy selective pressure associated with traditional bactericidal agents. In pathogens such as Escherichia coli, Salmonella enterica, and Acinetobacter baumannii, OmpR activity is closely linked to both pathogenicity and antimicrobial resistance. Therapeutic development focuses on small-molecule inhibitors, such as the experimental compound VSIS_039, which are designed to disrupt OmpR DNA-binding and downstream virulence pathways. Additionally, mutations in the OmpR regulon are known to mediate resistance to various antibiotics, including beta-lactams and antimicrobial peptides like TAT-RasGAP317-326. By inhibiting OmpR, researchers aim to re-sensitize resistant bacteria to existing clinical treatments while mitigating the severity of the primary infection.

Other names

Transcriptional regulatory protein OmpRResponse regulator protein OmpRkmtompB

Inhibition of DNA-binding activity; Allosteric modulation of the EnvZ/OmpR signaling cascade; Modulation of outer membrane permeability