Molecular Description of Gene Associated with Biofilms in Oral Klebsiella Isolated from Obese People.

Abstract

Background: Obesity is a chronic health condition resulting from excessive accumulation of body fat. It is related to an increased risk of chronic diseases such as diabetes, heart disease, and high blood pressure, and is often caused by an imbalance between calories consumed and expended.

Materials and Methods: This study aims to find relation between the presence of Klebsiella bacteria in the oral microbiota and obesity and the possibility of its association with other chronic diseases; it was conducted between November and December 2025, targeting obese individuals. Oral swab samples were collected to analyze the relationship between obesity and oral bacterial composition, with a focus on the presence of Klebsiella bacteria and genotypes associated with biofilm formation.

Results: The study included 65 participants, divided according to their body mass index (BMI): 2 participants had normal weight (3%), 17 were overweight (26%), 26 were obese (40%), and 20 were morbidly obese (31%). Diagnostic results showed that 10 of the 65 samples (13.38%) were positive for Klebsiella spp., indicating a relatively moderate prevalence of these bacteria in the mouths of obese individuals. To understand the mechanisms of pathogenesis, the presence of three key genes responsible for biofilm formation in these bacteria was analyzed: Only four isolates were positive for the rmpA gene, while only three isolates had the mrkD gene, and only two isolates had the mrkA gene.

Conclusion: The results of this study suggested  a potential association between obesity and the presence of K. pneumoniae in the oral cavity, as well as differences in the presence of genes associated with biofilm formation, which may reflect variation in the pathogenicity of these bacteria.