Recent Prevalence of Multi-Drug Resistant (MDR) Salmonella typhimurium from Tertiary Care Hospital of Lahore, Pakistan; Integrating 16S rRNA Profiling and In Silico Analysis
Discuss this preprint
Start a discussion What are Sciety discussions?Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
Multidrug-resistant (MDR) strains of Salmonella enterica serovar Typhimurium with biofilm-forming capability are important foodborne pathogens that pose a significant challenge to control and treatment. The present study was designed to explore the involvement of the second-messenger signaling gene adrA in biofilm formation and antimicrobial resistance in multidrug-resistant S. Typhimurium isolates. Approximately 2300 isolates were sampled from tertiary care hospitals. The isolates were subjected to antimicrobial susceptibility testing by the Kirby-Bauer disk diffusion method, and biofilm formation was assessed by the Congo red agar assay. The isolates were identified by conventional biochemical methods along with molecular identification by 16S rRNA analysis. Amplification and subsequent sequencing of the 16S rRNA gene and of the target gene adrA were done by polymerase chain reaction (PCR). Additionally, bioinformatics tools such as phylogenetic analysis, protein structure prediction, and docking were applied. All the isolates showed multidrug-resistant phenotypes with a high level of resistance to ampicillin, cefotaxime, and ciprofloxacin, but were sensitive to azithromycin and meropenem. All were able to form biofilm and were positive for the gene adrA . The phylogenetic analysis of Salmonella strains confirmed the conservation of these genes. Molecular docking analysis was carried out to show the interactions of the encoded proteins with the tested antibiotics. Finally, there was evidence that multidrug-resistant S. Typhimurium strains had high biofilm-forming abilities and contained important second messenger signaling genes that are linked with bacterial persistence. The results showed that the genes adrA could be associated with biofilm formation and antimicrobial resistance and could be used as a starting point for future research into how to control multidrug-resistant Salmonella infections.
