Engineering bacterial two-component system PmrA/PmrB to sense lanthanide ions.

Area of Science:

• Microbiology
• Synthetic Biology
• Biochemistry

Background:

• The Salmonella PmrA/PmrB two-component system naturally senses ferric ions using an iron(III)-binding motif.
• This system regulates gene expression in response to environmental iron levels.

Purpose of the Study:

• To engineer the PmrA/PmrB system for sensing lanthanide ions instead of iron.
• To demonstrate lanthanide sensing and gene regulation in live E. coli cells.

Main Methods:

• Replaced the native iron(III)-binding motif of the PmrA/PmrB system with a lanthanide-binding peptide sequence.
• Introduced the engineered system into E. coli for functional testing.

Main Results:

• The engineered PmrA/PmrB system successfully sensed lanthanide ions.
• The system regulated gene expression in response to lanthanide presence in E. coli.
• This represents the first reported instance of lanthanide sensing and response in live cells.

Conclusions:

• The PmrA/PmrB system can be successfully re-engineered for lanthanide ion sensing.
• This engineered system provides a novel platform for developing bacteria capable of sensing and responding to various metal ions.
• Potential applications include metal ion remediation and sequestration using engineered microorganisms.