Agricultural Biotechnology Journal

Agricultural Biotechnology Journal

Phenotypic ciprofloxacin resistance and detection of gyrA and parC genes in Enterococcus faecalis isolated from urinary tract infections in Baghdad, Iraq

Articles in Press

Document Type : Research Paper

Authors
Dijlah A. Alimeer 1
Heba Ameen Kadhom 2
Eman Thamer Garallah 3
Buthenia A. Hasoon 4
Majid S. Jabir 4
1 Al-Rusafa Third Directorate, Ministry of Education, Baghdad, Iraq
2 Department of Environmental Health, College of Energy and Environment, Al- Karkh University of Sciences, Baghdad, Iraq
3 Iraqi Centre for Cancer and Medical Genetic Research, Mustansiriyah University, Baghdad, Iraq
4 Collage of Applied Sciences, University of Technology, Baghdad, Iraq
10.22103/jab.2026.27345.1940
Abstract
Objective
One of the important causes of urinary tract infections (UTIs) is Enterococcus faecalis. This is especially true in hospitalized patients. It has been shown that ciprofloxacin resistance in E. faecalis can be caused by changes in the chromosomal genes encoding DNA gyrase and topoisomerase IV, as well as other resistance mechanisms. Therefore, the aim of this study was to determine the ciprofloxacin susceptibility profile of E. faecalis isolates isolated from urine samples. In addition, the identification of gyrA and parC genes associated with quinolone targets was the next aim of the study.
Materials and methods
Initially, 400 urine samples were collected from three hospitals in Baghdad. Among these 400 samples, 95 isolates were identified as Enterococcus faecalis. Among these 95 isolates, 20 (21.1%) were resistant to ciprofloxacin. VITEK 2 system and PCR were used for confirmation. MICs of ciprofloxacin were evaluated based on CLSI recommendations. gyrA and parC were subjected to amplification, and in silico docking was performed to examine ciprofloxacin interaction with DNA gyrase and topoisomerase IV.
Results
Ninety-five isolates of Enterococcus faecalis were identified from 400 urine samples. Twenty isolates (21.1%) showed ciprofloxacin MICs ranging from 64 to 512 μg/mL. While the rest (75 isolates, i.e. 78.9%) showed MICs between 2 and 4 μg/mL. The presence of gyrA and parC genes in the tested ciprofloxacin-resistant isolates was confirmed using PCR. The results show that the predicted docking score changed from -7.8 kcal/mol for the wild-type model to -3.89 kcal/mol for the mutant model. These changes indicate that a more unfavorable predicted interaction has occurred between ciprofloxacin and the mutant receptor. The results of docking analysis revealed that the predicted interactions of ciprofloxacin with the modeled mutant proteins, in comparison to the wild-type models were less favorable.
Conclusion
The results show that there is a correlation between detection of gyrA and parC genes and high-level ciprofloxacin resistance. However, to identify specific mutations and determine their association with the phenotype, it is necessary to sequence the quinolone resistance-determining regions.
Keywords
antimicrobial resistance
ciprofloxacin
Enterococcus faecalis
molecular docking
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Agricultural Biotechnology Journal

Articles in Press, Accepted Manuscript
Available Online from 22 August 2026