Transcription factor-based biosensors enlightened by the analyte

Area of Science:

• Environmental Science
• Molecular Biology
• Biotechnology

Background:

• Whole cell biosensors (WCBs) are crucial for environmental monitoring, relying on transcription factors (TFs) for pollutant detection.
• TF sensitivity and specificity are critical for WCB performance in identifying diverse analytes.

Purpose of the Study:

• To review TF families, their regulatory mechanisms, and structural/biochemical properties for environmental WCB development.
• To focus on TFs responding to aromatic compounds, metal ions, and antibiotics.
• To analyze TF structural domains for DNA recognition and effector binding.

Main Methods:

• Review of TF families including XylS-AraC, XylR-NtrC, LysR, MerR, ArsR, DtxR, Fur, NikR, TetR, and MarR.
• Analysis of TF structural domains involved in DNA binding and effector recognition.
• Examination of TF modular architecture and potential for engineering hybrid specificities.

Main Results:

• Identified conserved similarities in the DNA binding domains (DBDs) across various TF families.
• Observed diverse structures in effector binding domains corresponding to a wide range of analytes.
• Highlighted the modular nature of TFs as a basis for engineering novel specificities.

Conclusions:

• TF structural analysis reveals conserved DBDs and diverse effector binding domains, crucial for WCB design.
• The modular architecture of TFs offers potential for engineering hybrid DNA and effector specificities for advanced biosensors.
• Challenges remain in precisely correlating TF structural domains with specific functions for targeted engineering.