Skip to main content
padlock icon - secure page this page is secure

Free Content Species‐specific residues calibrate SoxR sensitivity to redox‐active molecules

Download Article:

In enterics, the transcription factor SoxR triggers a global stress response by sensing a broad spectrum of redox‐cycling compounds. In the non‐enteric bacteria Pseudomonas aeruginosa and Streptomyces coelicolor, SoxR is activated by endogenous redox‐active small molecules and only regulates a small set of genes. We investigated if the more general response in enterics is reflected in the ability of SoxR to sense a wider range of redox‐cycling compounds. Indeed, while Escherichia coli SoxR is tuned to structurally diverse compounds that span a redox range of −450 to +80 mV, P. aeruginosa and S. coelicolor SoxR are less sensitive to viologens, which have redox potentials below −350 mV. Using a mutagenic approach, we pinpointed three amino acids that contribute to the reduced sensitivity of P. aeruginosa and S. coelicolor SoxR. Notably these residues are not conserved in homologues of the Enterobacteriaceae. We further identified a motif within the sensor domain that tunes the activity of SoxR from enterics – inhibiting constitutive activity while allowing sensitivity to drugs with low redox potentials. Our findings highlight how small alterations in structure can lead to the evolution of proteins with distinct specificities for redox‐active small molecules.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Document Type: Research Article

Publication date: January 1, 2013

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more