The DosS-DosT/DosR Mycobacterial Sensor System

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• The DosS/DosR two-component system regulates the entry of Mycobacterium tuberculosis into a dormant state.
• DosR is a DNA-binding protein activated by phosphorylation from DosS or DosT.
• DosT is a sensor protein closely related to DosS, also involved in DosR-mediated dormancy.

Purpose of the Study:

• To review the structure, biophysical properties, and function of the DosS/DosT heme sensors.
• To explore the proposed roles of DosS and DosT as gas and redox state sensors.

Main Methods:

• Review of existing literature on the DosS/DosT system.
• Analysis of structural and biophysical data for DosS and DosT.
• Discussion of functional studies related to gas and redox sensing.

Main Results:

• DosT acts as a gas sensor, activated by low oxygen, NO, or CO binding in its ferrous state.
• DosS functions similarly as a gas sensor, with some evidence suggesting a role in redox sensing.
• Phosphorylated DosR binding to DNA triggers the expression of approximately fifty dormancy-linked genes.

Conclusions:

• The DosS/DosT system is crucial for regulating mycobacterial dormancy.
• DosS and DosT are heme-containing sensors with distinct but overlapping functions in gas detection.
• Further research is needed to fully elucidate the mechanisms of DosS and DosT in sensing and dormancy regulation.