Molecular docking and comparative transcriptome analysis of Fusarium oxysporum f.sp. cubense grown in 2,4-di-tert-butyl phenol amended medium deciphers the antifungal action of 2,4-di-tert-butyl phenol

Panama wilt, caused by Fusarium oxysporum f.sp. cubense, poses a severe threat to banana crops due to its invasive nature and the resilience of its reproductive structures. Traditional management strategies and current chemical interventions are proving ineffective against this pathogen, exacerbated by the emergence of resistance. In response to this challenge, recent advancements in bioinformatics have enabled the identification of microbial biomolecules with broad-spectrum activity against plant pathogens. This study explores the potential of biomolecules produced by the bacterial endophyte Bacillus licheniformis MW301654 to combat Fusarium oxysporum f. sp. cubense (Foc - S16). Through molecular docking analysis, 2,4-di-tert-butyl phenol and glafenine were identified as compounds with antifungal properties. Subsequent verification using the poisoned plate technique, confirmed the antifungal activity of 2,4-di-tert-butyl phenol. To elucidate the mode of action, comparative transcriptome analysis of Foc S16 grown in the presence of 2,4-di-tert-butyl phenol was conducted. The results revealed downregulation of key genes associated with signaling pathways crucial for the pathogen's survival and pathogenicity, including the cAMP pathway, MAPK pathway, calcineurin pathway, and Akt signaling pathway. Downregulation was also observed in genes related to the PIP2-DAG signaling pathway, the G protein alpha subunit, inositol monophosphates, calcineurin B subunit, calmodulin, and members of the MAPK signaling pathway. Furthermore, the downregulation of transcripts associated with the gamma-tubulin complex, tubulin alpha and beta chains, tubulin-binding cofactor A, cofilin, chitin synthase, actin cytoskeleton-regulatory complex proteins, and actin-like proteins contributed to the antifungal action against Foc - S16. In conclusion, 2,4-di-tertbutyl phenol from Bacillus licheniformis MW301654 presents a promising novel biomolecule with diverse antifungal mechanisms for the management of Fusarium oxysporum f.sp. cubense infections in banana crops.