The present invention relates to pathogenic bacteria, and is particularly concerned with treating, preventing or ameliorating bacterial infections using novel antibiotic compositions. The invention is especially useful for treating infections of Bacillus and Clostridia species, such as Clostridium difficile, Staphylococcus aureus and Mycobacterium spp. The invention extends to pharmaceutical compositions comprising such formulations. The invention also extends to methods for identifying aerobic Bacillus spp., which exhibit antibacterial activity against other bacteria, such as C. difficile, and to methods for isolating active antibacterial compositions from these aerobic Bacillus spp.
