Bacteriophage isolation from antibiotic-resistant bacterial strains

Antibiotic resistance is a serious public health problem that has caused increasing difficulties in treatment over time, resulting from the prolonged and repeated use of antibiotics. Hospitalacquired infections typically occur in patients with weakened immune systems, after surgical procedures, or in intensive care units (ICUs), where the use of catheters, ventilators, or other invasive devices creates favorable conditions for the spread and colonization of antibioticresistant bacteria. The treatment of hospital infections caused by antibiotic-resistant bacteria is often difficult and even impossible. Therefore, bacteriophages, which are used as an alternative method in treating infections caused by antibiotic-resistant bacteria, hold promise for the future. The targeted action of phages, especially when used in combination with antibiotics, could open new avenues for the treatment of hospital infections in the future. However, more clinical studies are needed to ensure the safety and effectiveness of phage therapy, and the safety, mechanisms of action, and applicability of the treatment must be thoroughly investigated. In this study, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Acinetobacter baumannii, Streptococcus pyogenes, Morganella morganii, and Enterobacter cloacae strains, which were resistant and isolated from various departments, intensive care units, and the Larval Debridement Clinic of the Traditional and Complementary Medicine Application and Research Center at Cerrahpaşa Medical Faculty, were used as host bacteria, and the isolation of phages from these bacteria was planned.No study in the literature has reported a method for isolating phages from hospital-origin resistant bacteria similar to the one used in this work. The method employed is original; it involves exposing the bacteria to thermal changes and mechanical stresses to disrupt their cell wall integrity, allowing phages to release and be liberated into the environment. As a result of the study, phages were isolated from P. aeruginosa, K. pneumoniae, and E. coli bacteria. The "dirty" phages obtained underwent several rounds of purification. After purification, lytic phages were successfully isolated from P. aeruginosa and K. pneumoniae. This novel method, with an uncertain success rate, is open to improvements and developments. Given that the isolation of phages from resistant bacteria is being attempted for the first time, this study is significant and requires further comprehensive research.