# Exploring the Relationship Between Biofilm Formation and Antibiotic Resistance Genes in Clinically Isolated Klebsiella pneumoniae

## TL;DR

This study shows that biofilm formation in Klebsiella pneumoniae is linked to increased expression of antibiotic resistance genes, suggesting a new approach for treating persistent infections.

## Contribution

The study reveals a novel connection between biofilm-associated genes and antibiotic resistance gene expression in clinical isolates of Klebsiella pneumoniae.

## Key findings

- All clinical isolates of Klebsiella pneumoniae were found to be biofilm formers.
- The presence of the mrkA gene was significantly associated with elevated expression of the blaSHV gene.
- Strains with the mrkA gene showed higher resistance gene expression, especially under neutral pH conditions.

## Abstract

Persistent pathogens pose a significant global health burden, contributing to increased morbidity and mortality rates worldwide. This study investigates the relationship between clinically relevant biofilm-associated and antibiotic resistance genes in Klebsiella pneumoniae isolates. Biofilm-forming capabilities of the isolates were evaluated, and their biomass was quantitatively analyzed. The presence of biofilm-associated and resistance genes (mrkA, blaSHV, blaTEM, and blaKPC) in the samples was identified using conventional PCR. Gene expression levels were quantified via RT-qPCR under acidic and neutral pH conditions, and the results were analyzed statistically to evaluate significance. All clinical isolates were found to be biofilm formers. PCR analysis revealed that a significant proportion of the isolates harbored the mrkA, blaSHV, and blaTEM genes, with prevalence rates of 78%, 89%, and 63%, respectively. In contrast, the blaKPC gene was absent. Statistical analysis revealed a significant (p = 0.0357) association between the presence of the mrkA gene and elevated expression of the blaSHV gene. Strains harboring the mrkA gene demonstrated higher resistance gene expression compared to mrkA-negative strains, particularly under neutral conditions (pH 7). In conclusion, these findings suggest that biofilm may contribute to antibiotic resistance not just by acting as a physical layer but also by modulating the expression of resistance genes. This observed relationship highlights the importance of designing novel therapies that can target both biofilm and resistance mechanisms to combat persistent infections.