Antibacterial potential of endophytic Streptomyces spp. isolated from peanut (Arachis hypogaea) roots: bioactiveprofiling and molecular docking studies

The worldwide escalation of antimicrobial resistance (AMR) necessitates the search for new bioactive agents from natural sources. Consequently, this study investigates the antimicrobial activity of endophytic Streptomyces spp. Eighteen Streptomyces isolates were recovered from sixteen peanut root samples using nitrate starch agar at 30 °C for 7 days. Among these, two strains, Streptomyces rochei RSA1 and Streptomyces sp. RSA2, exhibited significant antibacterial activity against both Gram-positive (Bacillus cereus and Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria, compared with six standard antibiotics. Nine metabolic bioactive compounds were identified using GC-MS. However, two compounds2-(butylthio) pyrimidine-4,6(1 H,5 H)-dione and 2,4-di-tert-butylphenol were particularly prominent (> 96% abundance). Functional groups were confirmed via FT-IR spectra. Molecular docking and dynamics simulations with relevant bacterial protein targets (PDB ID: 6FJH, 1O9G, 1J5E, and 9QT5) revealed strong hydrogen bonding and electrostatic interactions, with S. rochei RSA1 forming the most stable complex. Overall, peanut-derived endophytic Streptomyces represent promising sources of bioactive antibacterial metabolites for combating multidrug-resistant infections.