Islam, Md Shariful, Supti, Sumaiya Jahan, Tasnim, Faria, Hasan, Md Zahid, Nuryay, Mst Naharina, Tabassum, Nabida, Priota, Maysha Fahmeda, Moon, Md Jan Sadur Rahman, Alqahtani, Taha, Zaki, Magdi E.A., Sarker, Subir, and Hosen, Md Eram (2026) Mechanistic Insights Into the Inhibition of Clostridioides difficile Binary Toxin by Indolylmethyl Glucosinolate and Indole-3-Carbinol. Scientifica, 2026 (1).

Preview

PDF (Published Version) - Published Version Available under License Creative Commons Attribution. Download (5MB) | Preview

Abstract

Clostridioides difficile infection (CDI) remains a significant healthcare challenge, primarily due to its toxin-mediated pathogenesis that results in severe gastrointestinal complications. This study investigates the inhibitory potential of bioactive compounds derived from Brassica oleracea L., specifically targeting the CDTa subunit of the binary toxin, using both computational and experimental approaches. Molecular docking analysis identified indolylmethyl glucosinolate (−9.1 kcal/mol) and indole-3-carbinol (−8.75 kcal/mol) as top candidates, demonstrating high binding affinities to the CDTa protein. Stability and dynamic behavior of the ligand–protein complexes were further assessed through 100-ns molecular dynamics simulations, which confirmed their stable interactions. Thermodynamic evaluations using MM-GBSA calculations revealed favorable binding free energies, supporting their potential as effective inhibitors. In parallel, the antibacterial efficacy of these compounds was validated through in vitro antibacterial assays, where indolylmethyl glucosinolate and indole-3-carbinol exhibited maximum inhibition zones of 23.33 ± 0.67 mm and 22.67 ± 0.33 mm, respectively, at a concentration of 100 μg/mL. In MIC and MBC assays, both compounds showed significant antibacterial activity, with indolylmethyl glucosinolate demonstrating slightly higher potency (MIC: 10.33 ± 0.72 μg/mL; MBC: 23.33 ± 1.36 μg/mL) than indole-3-carbinol (MIC: 11.33 ± 0.27 μg/mL; MBC: 26.67 ± 3.60 μg/mL). Additionally, PCA and DCCM revealed distinct conformational stabilization patterns and correlated motion of CDTa upon ligand binding, supporting a potential antivirulence interaction. Moreover, ADMET analysis revealed differences in their pharmacokinetic and toxicity profiles, providing further insights into their therapeutic potential. Overall, these findings suggest that B. oleracea–derived compounds exhibit a direct antibacterial activity against C. difficile while also demonstrating computationally supported inhibition of CDTa, indicating a complementary antivirulence mechanism that may contribute to their therapeutic potential in CDI.

Item ID:	92142
Item Type:	Article (Research - C1)
ISSN:	2090-908X
Keywords:	antibacterial activity, Brassica oleracea, CDTa toxin, Clostridioides difficile, molecular docking, molecular dynamics simulation
Copyright Information:	This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Copyright © 2026 Ariful Islam et al. Scientifca published by John Wiley & Sons Ltd.
Date Deposited:	15 Jun 2026 23:45
Downloads:	Total: 1 Last 12 Months: 1
	More Statistics