Detection of Bacteria-Specific Metabolism Using Hyperpolarized [2-¹³C]Pyruvate

Area of Science:

• Biophysics
• Medical Imaging
• Microbiology

Background:

• Differentiating bacterial infections from other inflammatory conditions is clinically challenging.
• Current imaging techniques often focus on host immune responses, not direct microbial detection.
• Early diagnosis is crucial for effective patient outcomes.

Purpose of the Study:

• To develop a novel method for detecting bacteria-specific metabolism.
• To utilize hyperpolarized 13C magnetic resonance spectroscopy for real-time microbial metabolic visualization.
• To establish a metabolic signature for identifying bacterial pathogens.

Main Methods:

• Employed hyperpolarized (HP) 13C magnetic resonance spectroscopy.
• Visualized the real-time conversion of HP [2-13C]pyruvate to [1-13C]acetate.
• Tested the method in bacterial strains (Escherichia coli, Staphylococcus aureus) and mammalian cells.
• Validated findings using bacterial mutant strains.

Main Results:

• Identified rapid HP [2-13C]pyruvate to [1-13C]acetate conversion as a bacterial metabolic signature.
• Demonstrated this signature in both Gram-negative and Gram-positive bacteria.
• Confirmed the absence of this metabolic conversion in mammalian cells.
• Showed successful modulation of the conversion in mutant bacterial strains.

Conclusions:

• HP 13C magnetic resonance spectroscopy can detect bacteria-specific metabolism.
• The conversion of HP [2-13C]pyruvate to [1-13C]acetate serves as a reliable biomarker for bacterial pathogens.
• This technique offers a promising approach for direct microbial detection in clinical settings.