Isolation, purification, and characterization of lytic bacteriophages targeting Klebsiella pneumoniae strains isolated from Intensive Care Unit patients

• Grant number: 25/07942-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2025
• End date: September 30, 2026
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Maria Cristina da Silva Pranchevicius
• Grantee: Pedro Esposti Romano
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The emergence of antibiotic-resistant bacteria has become a critical global health challenge. Klebsiella pneumoniae, an opportunistic pathogen, primarily causes hospital-acquired infections, often affecting immunocompromised individuals or those requiring intensive care. Bacteriophages are considered one of the most promising alternative treatments to traditional antibiotic therapies, particularly for combating multidrug-resistant bacteria. This study aims to isolate lytic bacteriophages from hospital and urban wastewater that can infect and lyse K. pneumoniae strains resistant to carbapenems, obtained from Intensive Care Unit patients. The phages will be isolated, enriched, and purified using spot tests, double-layer agar, and/or strip drag assays. Comprehensive phage characterization will involve various analyses, including family prediction by PCR, morphology assessment by electron microscopy, determination of phage specificity using the plating efficiency method, adsorption and growth curve analysis, evaluation of thermal stability and resistance to different pH ranges, assessment of efficiency against biofilms, and sequencing and analysis of the complete genomes of selected phages. This research aims to contribute knowledge that may aid in controlling the evolution and dissemination of these pathogens, as well as the development of new therapeutic and sanitary strategies against clinically relevant bacteria.