Antimicrobial Activities of Compounds Produced by Newly Isolated Streptomyces Strains from Mountain Caves

: The ‘antibiotic crisis’, defined as appearance of microbial strains resistant to most, if not all, already known antibiotics, indicates that searching for previously unknown antimicrobial agents is crucial for further development of novel drugs which can be used to combat infections caused by bacteria and fungi. Bacteria living in untypical and extreme habitats appear to be a po-26 tentially reach source of such compounds. We have reported recently an isolation of newly identi-27 fied strains of Actinobacteria from the Szczelina Chochołowska cave (Tatra Mountains, Poland) . Some of them produced molecules revealing antibacterial, antifungal and anticancer properties. Here, we describe further characterization of the selected strains. Their microbiological properties, ability to form biofilms, and antimicrobial activities against various strains of bacteria and fungi are reported. The selected strains of newly isolated Actinobacteria belonging to the genus Streptomyces appear a promising source of previously unknown antimicrobial agents. have the version manuscript.