Bacteria Isolated from Antarctic Permafrost are Efficient Antibiotic Producers

Resumo

Nontraditional sources were shown to be promising for obtaining bacterial isolates characterized by efficient production of antibiotics, including those affecting the strains with multidrug resistance. From Antarctic permafrost, 32 bacterial strains were isolated, and their ability to synthesize antimicrobal compounds efficient against 12 test strains, including the ones with multidrug resistance, was studied in submerged cultures. Out of 13 strains producing antibiotic compounds with different spectra of action, seven were chosen for further study. Their species identification was carried out by microbiological techniques and by analysis of their 16S rRNA gene sequences. Six strains of spore-forming bacteria were identified as Bacillus species (B. licheniformis, B. mojavensis, B. safensis, and B. subtilis), while one strain was identified as Gordonia terrae. Antimicrobial activity of two B. mojavensis strains (INA 01149 and INA 01151), two B. safensis strains (INA 01153 and INA 01154), and B. licheniformis strain INA 01155 against the antibiotic-resistant tester strain Leuconostoc mesenteroides VKPM B-4177 (VR) was revealed. Antibiotic activity of two B. safensis strains (INA 01153 and INA 01154) against tester bacteria, including Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus INA 00761 with multidrug resistance has not been reported previously. Antibiotic producers isolated from Antarctic permafrost samples are of interest to medicine due to the global issue of increasing antibiotic resistance of pathogenic bacteria.