New chemical blockers target a tuberculosis enzyme with species-specific promise

Tuberculosis remains a major global killer, and researchers are hunting for new ways to stop Mycobacterium tuberculosis (Mtb) at both active and dormant stages. In work led by corresponding author Lina Riegler-Berket, scientists focused on proteins that handle lipid metabolism in the bacterium, because those proteins help Mtb survive and persist. One such protein is the monoacylglycerol lipase Rv0183, which is involved in breaking down fats that the bacterium uses for energy and survival. To find compounds that block this enzyme, the team used high-throughput screening at the European Lead Factory. That search uncovered a novel chemotype built around a hydroxypyrrolidine ring. These new molecules showed potent inhibition of Rv0183 in laboratory tests and produced promising results in whole cell bacterial studies, meaning the compounds did more than just affect the isolated protein — they also impacted live bacterial cells. The study sets out not only a new chemical starting point but also a path to understand exactly how these molecules interfere with a critical Mtb enzyme.

After finding the hydroxypyrrolidine-based hits, the researchers turned to structural and computational tools to understand how the inhibitors work. Co-crystallization studies were carried out with Rv0183, revealing that the compounds bind inside the enzyme’s lipase pocket through non-covalent interactions; these structural snapshots explain the physical basis for inhibition. To check whether the bacterial enzyme’s binding cavity differs from the human counterpart, the team used comparative analysis augmented by AI-driven 3D-point-cloud approaches to map cavities and shapes. That work distinguished Rv0183’s ligand-binding cavity from that of human monoacylglycerol lipase, suggesting the possibility of species-selective inhibition. Molecular docking simulations were then used to test and validate the experimental binding affinities and to predict the most likely binding modes. Together, these X-ray co-crystallization and computational docking results support the idea that the hydroxypyrrolidine chemotype can bind strongly and specifically to Rv0183.

The combination of experimental structural biology and modern computational methods in this study provides a clear picture of how the new hydroxypyrrolidine-based inhibitors engage Rv0183. By showing both a structural basis for inhibition and evidence that the bacterial binding site differs from the human enzyme, the research points to a path for developing drugs that hit Mtb while sparing human proteins. That species-specific targeting could reduce off-target effects and make treatments safer. Importantly, because Rv0183 plays roles during both active infection and dormancy, inhibitors that reliably block this enzyme might help eliminate bacteria that hide in a dormant state and later cause disease resurgence. The work led by Lina Riegler-Berket therefore represents a significant step toward structure-guided antitubercular therapies that combine high-throughput discovery, X-ray co-crystallization, AI-driven 3D-point-cloud comparison, and molecular docking to prioritize compounds for further development.