Antimicrobial Potential of Culturable Soil Bacteria from the Kingdom of Bahrain

The global rise of antimicrobial resistance has intensified the search for new antibacterial agents from natural environments. Soil microbial communities have historically served as important reservoirs of bioactive metabolites, yet many regions remain insufficiently explored. This study surveyed soil samples across the Kingdom of Bahrain to identify culturable bacterial isolates exhibiting inhibitory activity against clinically relevant Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp., and Escherichia coli (ESKAPEE) pathogens and to taxonomically characterize active isolates using 16S ribosomal RNA (rRNA) gene sequencing. A total of 45 soil samples were collected from diverse locations across the country. Culturable bacteria were isolated using standard microbiological methods and screened for antimicrobial activity using a competition plate assay against reference strains representing the ESKAPEE group of pathogens. Isolates demonstrating reproducible antagonistic activity were subsequently subjected to molecular identification through amplification and sequencing of the 16S rRNA gene. Screening revealed that 65 isolates exhibited consistent inhibitory activity against at least one ESKAPEE pathogen. Taxonomic analysis revealed a phylogenetically diverse collection of bacteria spanning multiple genera and phyla, including members of Bacillota, Pseudomonadota, and Bacteroidota. Several isolates belonged to well-known antimicrobial-producing lineages such as Bacillus and related Bacillaceae genera, while others represented comparatively underexplored environmental taxa, including Rossellomorea, Paenibacillus, Photobacterium, and Olivibacter. The observed antagonistic activity likely reflected diverse ecological strategies. Collectively, these findings demonstrated that soil microbiota from the Kingdom of Bahrain harbor diverse culturable bacteria with antibacterial activity against clinically important pathogens, providing an initial collection of antagonistic soil isolates for further characterization.