UC Merced Undergraduate Research Journal

Bacteria are some of the first organisms to ever exist in the biosphere, being prokaryotic organisms, they have been present on Earth for the past 3 billion years. Soon afterward, however, certain retroviruses evolved to infect these organisms soon becoming the most populous entity in the biosphere. For decades, researchers have delved into the various interactions between bacteria and bacteriophages due to their coevolutionary dynamics. Through this research, scientists eventually were able to discover a plethora of various mechanisms that bacteria have utilized to prevent bacteriophage infections, including but not limited to, receptor inactivation, modification, clustering, and CRISPR-Cas systems. Bacteriophages have developed superb countermeasures to these defenses over billions of years of coevolution. Scientists are trying to understand these coevolutionary dynamics to develop better potential antibiotic treatments using bacteriophages, as the prevalence of antibiotic-resistant bacteria has become a critical issue in modern healthcare. The excessive utilization of antibiotics has accelerated the prevalence of resistant strains of bacteria, rendering conventional antibiotics ineffective against once-treatable infections. This phenomenon can dramatically reduce patient outcomes and pose a substantial challenge to public health systems. In response to this crisis, virologists are actively exploring alternative therapeutic strategies to combat antibiotic resistance. One such novel approach that is becoming increasingly more studied is bacteriophage therapy, which utilizes viruses that selectively target and kill specific pathogenic bacterial strains. By sparing beneficial bacteria and offering a safe solution, bacteriophage therapy presents a promising avenue for addressing the growing threat of antibiotic resistance.