Bacteriófagos ambientais com atividade lítica frente a Klebsiella pneumoniae multirresistente: estudo na lagoa do Porangabussu, Fortaleza-CE

Abstract

The increase in bacterial resistance represents one of the greatest challenges faced by contemporary public health due to the emergence of multidrug-resistant (MDR) bacteria. In this context, the development of new therapeutic approaches that are both effective and cost-efficient for controlling these infections becomes essential. Klebsiella pneumoniae, an opportunistic Gram-negative bacterium, is associated with severe infections such as pneumonia, septicemia, and urinary tract infections. Phage therapy, a pre-existing approach that uses viruses specific to infecting and destroying bacteria, has reemerged as a promising therapeutic alternative. However, this form of treatment, despite being long-established, remains poorly explored. The aim of this study was to isolate, identify, and characterize bacteriophages with lytic potential against multidrug-resistant Klebsiella pneumoniae strains. For this purpose, water samples were collected from the Porangabussu lagoon in Fortaleza, Ceará, which were treated with chloroform, centrifugation, and filtration. The presence of bacteriophages in the enriched samples was verified using the spot test technique, through the formation of bacterial growth inhibition halos. Bioinformatics techniques were applied for the identification of target genes and the design of specific primers for the molecular diagnosis of bacteriophages. Three primers were designed: ter, cap, and ack. Bacteriophage samples underwent nucleic acid extraction using the Ribospin™ vRD kit (GeneAll®). Real-time PCR (qPCR) was performed, followed by two consecutive nested qPCRs for each of the selected genes. The results indicated the presence of bacteriophages with therapeutic potential against multidrug-resistant Klebsiella pneumoniae strains in the evaluated lagoon water. The cap and ack primers were effective in the early molecular diagnosis of these bacteriophages, and their use opens new perspectives for optimizing methodologies aimed at the isolation of novel phages