Nanoscale Direct-to-Biology Optimization and Structural Insights into Selective S. aureus TrmD Inhibitors.

Area of Science:

• Medicinal Chemistry
• Microbiology
• Structural Biology

Background:

• TrmD is essential in bacteria like Staphylococcus aureus, a significant human pathogen.
• Developing selective inhibitors for bacterial TrmD is crucial for new antimicrobial therapies.

Purpose of the Study:

• To identify and characterize selective inhibitors of Staphylococcus aureus TrmD.
• To provide structural insights into inhibitor binding for future drug design.

Main Methods:

• High-throughput nanomole-scale synthesis (nanoSAR) using copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC).
• Direct-to-biology assay for inhibitor screening.
• Cell-based assays to evaluate antibacterial activity and selectivity.
• Cocrystallization to determine the inhibitor-TrmD complex structure.

Main Results:

• Identified selective S. aureus TrmD inhibitors with nanomolar to low micromolar activity.
• A lead compound selectively inhibited S. aureus growth in cell-based assays without affecting Gram-negative bacteria.
• Determined the crystal structure of S. aureus TrmD bound to an inhibitor, revealing the binding mode.

Conclusions:

• The identified inhibitors show promise as selective agents against S. aureus.
• Structural data facilitates structure-guided optimization for enhanced efficacy and selectivity.
• This work provides a foundation for developing novel anti-staphylococcal therapeutics targeting TrmD.