Detection via in vitro amplification of lasR gene associated with virulent attribute of Pseudomonas aeruginosa from acute pulmonary infections

Abstract

Pseudomonas aeruginosa is the most ubiquitous pulmonary pathogen of human which causes successfully unscrupulous infections in patients with the suppressed immune system of every age group and is considered as the first or second key pathogen in the research. The most lethal and persistent pathogen that caused the acute ventilator-acquired pneumonia (VAP) infection is P. aeruginosa. The Quorum sensing (QS) system is present in P. aeruginosa which regulates the expression of various virulence factors. In the current study, the contribution of lasR gene of pathogenic P. aeruginosa responsible for acute pulmonary infections was investigated. The objectives of the current work were; to screen the pathogenic P. aeruginosa from acute (VAP) through endotracheal tract (ETT) secretions and blood, to identify and characterize pathogenic strains by biochemical testing and virulence assays and to detect lasR, gene of P. aeruginosa responsible from acute pulmonary infections. The samples included secretions (Endotracheal tract) and Blood samples from patients with acute Ventilator-associated pneumonia (VAP). Samples were provided by the Microbiology laboratory of GCU Lahore. Total four strains of P. aeruginosa were selected as most virulent after confirmatory test of antibiotic sensitivity and virulence assays. Mutation was induced in wild strains via ethidium bromide. Molecular characterization of P. aeruginosa strains and lasR gene was done. Sequence analysis results after BLAST at NCBI confirmed P. aeruginosa strains and the presence of lasR gene which is involved in multiple virulence factors and is responsible for acute pulmonary infections. Wild and mutant strains of this bacterium showed resistance to the most commonly used antibiotics. Hence, it can be concluded that P. aeruginosa is involved in hospital-acquired and ventilator-acquired pneumonia and is a highly efficient multidrug-resistant pathogenic bacteria. Also, lasR gene sequence can be used as the diagnostic marker to identify the virulent lasR gene sequence from this opportunistic pathogen in the future.