Mechanism-Based Inhibitors: Development of a High Throughput Coupled Enzyme Assay to Screen for Novel Antimalarials

Area of Science:

• Biochemistry
• Parasitology
• Drug Discovery

Background:

• High-throughput screening (HTS) is crucial for identifying novel drug lead molecules.
• The purine salvage pathway is essential for the survival of the malarial parasite Plasmodium falciparum.
• Targeting parasite-specific metabolic pathways offers a strategy for antimalarial drug development.

Purpose of the Study:

• To develop a robust HTS assay for the Plasmodium falciparum purine salvage pathway.
• To identify novel inhibitors of parasite purine salvage enzymes.
• To find new therapeutic strategies against malaria.

Main Methods:

• Developed a coupled HTS assay using recombinant hypoxanthine guanine phosphoribosyl transferase (HGPRT) from P. falciparum and human inosine monophosphate dehydrogenase (IMPDH).
• The assay mimics a key step in the parasite's purine salvage pathway.
• Screened for compounds that inhibit the activity of these coupled enzymes.

Main Results:

• Successfully established a robust HTS assay meeting stringent criteria.
• Identified novel chemical entities with inhibitory activity against the parasite's purine salvage pathway.
• These inhibitors demonstrate potential for killing the malaria parasite.

Conclusions:

• The developed HTS assay is effective for identifying inhibitors of the Plasmodium falciparum purine salvage pathway.
• Novel inhibitors targeting this pathway were discovered, offering a promising avenue for antimalarial drug development.
• This approach provides a foundation for further investigation into new treatments for malaria.