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Determination of virulence and multidrug resistance genes with polymerase chain reaction method in
Şükran Saba Çopur1, Fikret Şahin2, Jülide Sedef Göçmen1
1Department of Medical Microbiology, Faculty of Medicine, Başkent University, Ankara, Turkey.
Background/Aim:
Enterococci play an important role in nosocomial infections. Therefore, this study investigates multidrug resistance (MDR)1 gene areas in the pathogenicity of enterococci and virulence genes in both vancomycin-sensitive enterococci (VSE) and vancomycin-resistant enterococci (VRE) strains.
Materials And Methods:
Virulence genes and MDR genes of enterococci were investigated by polymerase chain reaction (PCR).
Results:
We evaluated a total of 116 isolates, 93 being VRE and 23 being VSE. In this study, 95.6% of VRE (n = 93) were Enterococcus faecium (n = 89) and 4.3% were E. faecalis (n = 4), while 17.4% of VSE (n = 23) were E. faecium (n = 4) and 82.6% were E. faecalis (n = 19). The vanA MDR1 gene was detected in all VRE isolates. Among virulence genes, esp and hyl were detected in E. faecium, an enterococcus with the highest resistance to vancomycin, and gelE was detected in E. faecalis, an enterococcus with the highest sensitivity to vancomycin. Three or more virulence genes were identified only in VSE strains. We consider that it is a significant result that VSE had more virulence genes than VRE. Only esp was seen in VRE E. faecium strains.
Conclusion:
This study includes experimental results on the association of virulence characteristics in VRE and VSE strains.
Insights
Vancomycin-resistant enterococci (VRE) and vancomycin-sensitive enterococci (VSE) were analyzed for virulence and multidrug resistance (MDR) genes. VSE strains exhibited a higher number of virulence genes compared to VRE strains.
Area of Science:
- Microbiology
- Infectious Diseases
- Genetics
Background:
- Enterococci are significant causes of hospital-acquired infections.
- Multidrug resistance (MDR) and virulence factors in enterococci are critical for infection control.
- Understanding these factors in both vancomycin-sensitive (VSE) and vancomycin-resistant (VRE) strains is essential.
Purpose of the Study:
- To investigate multidrug resistance (MDR) gene areas and virulence genes in VSE and VRE strains.
- To compare the prevalence of specific virulence genes between VSE and VRE.
- To elucidate the genetic basis of pathogenicity in enterococcal infections.
Main Methods:
- Polymerase chain reaction (PCR) was employed to detect virulence and MDR genes.
- A total of 116 enterococcal isolates were analyzed, comprising 93 VRE and 23 VSE.
- Species identification and gene presence were systematically evaluated.
Main Results:
- The vanA MDR gene was present in all VRE isolates.
- Enterococcus faecium was the predominant VRE species, while Enterococcus faecalis was the dominant VSE species.
- Virulence genes esp and hyl were found in VRE E. faecium, and gelE in VSE E. faecalis. Notably, VSE strains harbored more virulence genes (≥3) than VRE strains.
Conclusions:
- VSE strains demonstrated a greater diversity of virulence genes compared to VRE strains.
- The findings highlight an inverse relationship between the number of virulence genes and vancomycin resistance in certain enterococcal species.
- This study provides experimental data on the association between virulence characteristics and resistance profiles in enterococci.
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