Real-Time Intracellular Bacterial Metabolism During Shigella Infection Using Hyperpolarized [2-¹³C]Pyruvate

Intracellular bacterial infections are challenging to study metabolically, as traditional methods often rely on indirect indicators. Hyperpolarized magnetic resonance spectroscopy (MRS) enables noninvasive, real-time metabolic monitoring, while being able to distinguish between pathogenic bacterial metabolism and host metabolism. Using dDNP-NMR, we demonstrate real-time conversion of hyperpolarized [2-¹³C]pyruvate to [1-¹³C]acetate within Shigella-infected HeLa cells. The conversion of hyperpolarized [1,4-¹³C₂]fumarate to [1,4-¹³C₂]malate was used to verify host cell integrity during infection, indicating that Shigella metabolism occurs within intact host cells. These findings highlight the potential of dDNP-NMR to provide deeper insights into the metabolic dynamics of bacterial infections, offering a powerful tool for studying bacterial-host interactions at a cellular level and facilitating the development of more precise therapeutic strategies for targeting infectious diseases.