Long before the advent of antibiotics, bacteria had already begun to develop remarkable resistance strategies. In an exciting discovery, researchers have uncovered a bacterial strain known as Psychrobacter, found in 5,000-year-old ice layers within a cave, showcasing resistance to ten modern antibiotics.
This ancient microorganism not only demonstrates resistance but also possesses promising enzymatic activities, enabling it to inhibit the growth of ‘superbugs,’ which are resistant to multiple antibiotics. Additionally, the genetics of this strain offers valuable insights into the evolutionary origins of antibiotic resistance.
Bacteria have shown an incredible ability to adapt to Earth’s most extreme environments, from scorching deserts to frigid ice caves. These unique habitats host diverse microorganisms that present a wealth of genetic diversity, much of which remains unexplored.
In Romania, researchers have investigated the antibiotic resistance profiles of this ancient strain recently discovered in the Scarisoara Ice Cave. Their findings could pave the way for innovative strategies to combat the rise of antibiotic resistance and enhance our understanding of how such resistance evolves and disseminates naturally. Their exciting research has been documented in Frontiers in Microbiology.
Dr. Cristina Purcarea, a senior scientist at the Institute of Biology Bucharest, highlighted, “The Psychrobacter SC65A.3 strain, despite its ancient roots, exhibits resistance to several modern antibiotics and carries over 100 resistance-related genes.” She further noted its ability to inhibit the growth of significant antibiotic-resistant superbugs while showcasing important enzymatic activities with considerable biotechnological potential.
This particular strain belongs to the genus Psychrobacter, which includes bacteria that thrive in cold environments and can occasionally cause infections in humans and animals. Dr. Purcarea and her team meticulously drilled a 25-meter ice core from what is known as the Great Hall of the cave, representing a timeline of 13,000 years. To ensure the integrity of their samples, they carefully transported the ice fragments in sterile bags, keeping them frozen until reaching the lab.
In the lab, researchers isolated various bacterial strains and sequenced their genomes to identify the genes responsible for survival in low temperatures and those that confer antimicrobial resistance and activity. They examined the SC65A strain’s resistance against 28 antibiotics from ten different classes commonly used to treat bacterial infections.
Dr. Purcarea emphasized the significance of their findings, stating, “The ten antibiotics we identified resistance to are widely utilized in both oral and injectable therapies for treating various serious bacterial infections in clinical settings.” These antibiotics include rifampicin, vancomycin, and ciprofloxacin, which are effective against diseases such as tuberculosis, colitis, and urinary tract infections.
Remarkably, SC65A.3 is the first Psychrobacter strain to exhibit resistance to specific antibiotics, including trimethoprim, clindamycin, and metronidazole. This discovery not only sheds light on ancient bacterial resilience but also inspires hope for future advancements in combating antibiotic resistance.
