Cryptococcosis is an invasive infection that accounts for 15% of AIDS-related fatalities. Still, treating cryptococcosis remains a significant challenge due to the poor availability of effective antifungal therapies and emergence of drug resistance. Interestingly, protease inhibitor components of antiretroviral therapy regimens have shown some clinical benefits in these opportunistic infections. We investigated Major aspartyl peptidase 1 (May1), a secreted Cryptococcus neoformans protease, as a possible target for the development of drugs that act against both fungal and retroviral aspartyl proteases. Here, we describe the biochemical characterization of May1, present its high-resolution X-ray structure, and provide its substrate specificity analysis. Through combinatorial screening of 11,520 compounds, we identified a potent inhibitor of May1 and HIV protease. This dual-specificity inhibitor exhibits antifungal activity in yeast culture, low cytotoxicity, and low off-target activity against host proteases and could thus serve as a lead compound for further development of May1 and HIV protease inhibitors.

• MeSH
• Antifungal Agents chemistry   metabolism   pharmacology   MeSH
• Aspartic Acid Proteases antagonists & inhibitors   genetics   metabolism   MeSH
• Cryptococcus neoformans enzymology   MeSH
• Fungal Proteins antagonists & inhibitors   genetics   metabolism   MeSH
• HIV Protease chemistry   metabolism   MeSH
• HIV enzymology   MeSH
• Fungi drug effects   MeSH
• Catalytic Domain MeSH
• Crystallography, X-Ray MeSH
• Drug Evaluation, Preclinical MeSH
• Recombinant Proteins biosynthesis   chemistry   isolation & purification   MeSH
• Molecular Dynamics Simulation MeSH
• Substrate Specificity MeSH
• Binding Sites MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• Antifungal Agents MeSH
• Aspartic Acid Proteases MeSH
• Fungal Proteins MeSH
• HIV Protease MeSH
• Recombinant Proteins MeSH