MarR family proteins sense sulfane sulfur in bacteria

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• The multiple antibiotic resistance regulator (MarR) protein family regulates bacterial metabolism and antibiotic resistance.
• Existing modulators do not fully explain MarR protein activities.
• Recent findings indicate MarR proteins sense sulfane sulfur, impacting gene expression.

Purpose of the Study:

• To review MarR family proteins that sense sulfane sulfur.
• To discuss the mechanisms by which sulfane sulfur modulates MarR protein activity.
• To highlight sulfane sulfur as an emerging regulator of gene expression.

Main Methods:

• Literature review of studies on MarR family proteins and sulfane sulfur sensing.
• Analysis of chemical reactions between sulfane sulfur and protein thiols.
• Comparison of sulfane sulfur sensing with reactive oxygen species (ROS) sensing mechanisms.

Main Results:

• Several MarR family proteins detect sulfane sulfur species (zero-valent sulfur, persulfides, polysulfides).
• Sulfane sulfur reacts with cysteine thiols in MarR proteins, forming modifications like persulfides and disulfide bonds.
• Sensing mechanisms for sulfane sulfur overlap with those for ROS, involving disulfide bond formation.

Conclusions:

• Sulfane sulfur is a significant modulator of MarR family protein function.
• The sensing mechanisms are relevant to other proteins detecting sulfane sulfur.
• Sulfane sulfur represents a novel pathway for bacterial gene regulation.