# A Nitroreductase‐Activatable Lapachol Against Bacillus subtilis Unveils Antimicrobial Specificity

## TL;DR

A new prodrug of lapachol is activated only in bacteria, reducing toxicity to human cells and offering a potential solution to antibiotic resistance.

## Contribution

A nitroreductase-activatable lapachol prodrug that selectively targets bacteria with minimal mammalian toxicity.

## Key findings

- The prodrug releases lapachol in Bacillus subtilis via nitroreductase activity.
- The prodrug shows >10-fold selectivity for bacterial over mammalian cells.
- Colony formation assays confirm antibacterial efficacy comparable to free lapachol.

## Abstract

Lapachol is a natural product with antimicrobial activity. Though promising for combating antimicrobial resistance, lapachol has toxicity to mammalian cells, which will cause severe side effects in vivo. To mitigate this, we developed alapachol prodrug which is dependent on the action of nitroreductase—an enzyme expressed in bacteria but not healthy mammalian cells. We observed release of lapachol in vitro by purified nitroreductase and in the gram‐positive bacterial strain, Bacillus subtilis. Colony formation assays in Bacillus subtilis indicated release of lapachol, achieving comparable levels of toxicity as free lapachol. Lastly, minimal toxicity of our prodrug was observed in mammalian cell culture, demonstrating a >10‐fold selectivity for bacteria over healthy mammalian cells.

A nitroreductase‐activatable lapachol prodrug overcomes toxicity to mammalian cells b selectively releases the antimicrobial natural product only in bacteria, addressing antimicrobial resistance. Enzymatic reduction in Bacillus subtilis triggers self‐immolative uncaging to restore antibacterial activity while sparing healthy cells.© 2026 WILEY‐VCH GmbH