β-Glucuronidase-IN-1 is a potent, selective, uncompetitive, and orally active E. coli bacterial β-glucuronidase inhibitor, exhibiting an IC50 and a Ki of 283 nM and 164 nM, respectively.IC50 & Target: IC50: 283 nM (E. coli?β-glucuronidase)Ki: 164 nM (E. coli?β-glucuronidase)In Vitro: β-Glucuronidase-IN-1 (Inhibitor 1) (0.01-100 μM) inhibits E. coli?β-glucuronidase activity as a dose-dependent manner and exhibits an IC50 and a Ki value with 283 nM and 164 nM, respectively.β-Glucuronidase-IN-1 (100 μM; 24-72 hours) maintains potent efficacy in living bacterial cells (EC50=17.7 nM), it does not affect bacterial cell growth under aerobic or anaerobic conditions or killing mammalian epithelial cells.In Vivo: β-Glucuronidase-IN-1 (oral gavage; 10 μg; twice per day; 11 days) protects the mouse GI epithelium from CPT-11–induced damage and protects the glandular structure of CPT-11-treated intestinal tissues.