Original Article

Immunological and molecular detection of biofilm formation and antibiotic resistance genes of Pseudomonas aeruginosa isolated from urinary tract

Abstract

Background and Objectives: Pseudomonas aeruginosa (P. aeruginosa) is one of the most common causes of hospital-acquired infections. It is associated with high morbidity and healthcare costs, especially when appropriate antibiotic treatment is delayed. Antibiotic selection for patients with P. aeruginosa infections is challenging due to the bacteria's inherent resistance to many commercially available antibiotics. This study investigated antibiotic-resistance genes in isolated bacteria, which play a key role in disease pathogenesis.
Materials and Methods: 100 samples out of the 140 samples collected from urinary tract infections (UTIs) cases between December 15th, 2022, and April 15th, 2023, were included in the study. Identification of bacterial isolates was based on colony morphology, microscopic examination, biochemical tests, and the Vitek-2 system. Antibiotic resistance genes; Aph(3)-llla, ParC, Tet/tet(M), and aac(6´)-Ib-cr were tested by polymerase chain reaction (PCR).
Results: The obtained results were based on bacterial identifications of 81 clinical samples. Only 26 (32%) of these isolates were P. aeruginosa, 21 (26%) were Escherichia coli, and 18 (22.2%) were other bacteria. These isolates were used to detect four genes including tet(M), Aph(3)-llla, Par-c, and aac(6´)-Ib-cr. Four types of primers were used for PCR detection. The results showed that 11/14 (78.57%) carried the tet(M) gene, 10/14 (71.42%) carried the Aph(3)-llla gene, 14/14 (100%) carried the Par-c gene, and 10/14 (71.42%) of the isolates carried the aac(6´)-Ib-cr gene. The biofilm formation examining the esp gene, showed that 9 (64.28) isolates carried this gene.
Conclusion: The inability of antibiotics to penetrate biofilms is an important factor contributing to the antibiotic tolerance of bacterial biofilms.

1. Andriankaja OM, Barros SP, Moss K, Panagakos FS, DeVizio W, Beck J, et al. Levels of serum interleukin (IL)-6 and gingival crevicular fluid of IL-1beta and prostaglandin E(2) among non-smoking subjects with gingivitis and type 2 diabetes. J Periodontol 2009; 80: 307-316.
2. Sathe N, Beech P, Croft L, Suphioglu C, Kapat A, Athan E. Pseudomonas aeruginosa: Infections and novel approaches to treatment “Knowing the enemy” the threat of Pseudomonas aeruginosa and exploring novel approaches to treatment. Infect Med (Beijing) 2023; 2: 178-194.‏
3. Arularasi Aberna R, Prabakaran K. Evaluation for the association of virulence determinants among E. faecalis with its clinical outcome. Int J Biol Med Res 2011; 2: 523-527.
4. Atabek A (2006). Investigating bacterial outer membrane polymers and bacterial interactions with organic molecules using atomic force microscopy. Worcester Polytechnic Institute.
5. Bennett PM. Plasmid encoded antibiotic resistance: acquisition and transfer of antibiotic resistance genes in bacteria. Br J Pharmacol 2008; 153 Suppl 1(Suppl 1): S347-S357.
6. Azucena E, Mobashery S. Aminoglycoside-modifying enzymes: mechanisms of catalytic processes and inhibition. Drug Resist Updat 2001; 4: 106-117.
7. Bahgat MM, Elbialy AA, Zaky MMM, Toubar SME. Prevalence of antibiotic resistant aerobic bacteria isolated from Surgical wounds of inpatients at Zagazig university hospitals, Egypt. Int J Curr Microbiol Appl Sci 2015; 4: 460-472.
8. Baker RJ, Senior H, Clemenger M, Brown EA. Empirical aminoglycosides for peritonitis do not affect residual renal function. Am J Kidney Dis 2003; 41: 670-675.
9. Balaban N, Cirioni O, Giacometti A, Ghiselli R, Braunstein JB, Silvestri C, et al. Treatment of Staphylococcus aureus biofilm infection by the quorum-sensing inhibitor RIP. Antimicrob Agents Chemother 2007; 51: 2226-2229.
10. Gajdács M, Baráth Z, Kárpáti K, Szabó D, Usai D, Zanetti S, et al. No correlation between biofilm formation, virulence factors, and antibiotic resistance in Pseudomonas aeruginosa: results from a laboratory-based in vitro study. Antibiotics (Basel) 2021; 10: 1134.‏
11. Baqai R, Aziz M, Rasool G. Urinary tract infection in diabetic patients and biofilm formation of uropathogens. Infect Dis J Pak 2008; 17: 7-9.
12. Barnett MJ, Fisher RF, Jones T, Komp C, Abola AP, Barloy-Hubler F, et al. Nucleotide sequence and predicted functions of the entire Sinorhizobium meliloti pSymA megaplasmid. Proc Natl Acad Sci U S A 2001; 98: 9883-9888.
13. Baron EJ. Rapid identification of bacteria and yeast: summary of a national committee for clinical laboratory standards proposed guideline. Clin Infect Dis 2001; 33: 220-225.
14. Barrett AJ, Woessner JF, Rowling ND (2004). Handbook of proteolytic enzymes, Volume 1. 2th ed. Academic press. https://shop.elsevier.com/books/handbook-of-proteolytic-enzymes-volume-1/barrett/978-0-12-079611-3
15. Baucheron S, Chaslus-Dancla E, Cloeckaert A. Role of TolC and parC mutation in high-level fluoroquinolone resistance in Salmonella enterica serotype Typhimurium DT204. J Antimicrob Chemother 2004; 53: 657-659.
16. Saeli N, Jafari-Ramedani S, Ramazanzadeh R, Nazari M, Sahebkar A, Khademi F. Prevalence and mechanisms of aminoglycoside resistance among drug-resistant Pseudomonas aeruginosa clinical isolates in Iran. BMC Infect Dis 2024; 24: 680.
17. Caiazza NC, O'Toole GA. Alpha-toxin is required for biofilm formation by Staphylococcus aureus. J Bacteriol 2003; 185: 3214-3217.
18. Tendolkar PM, Baghdayan AS, Shankar N. The N-Terminal domain of enterococcal surface protein, Esp, is sufficient for Esp-Mediated Biofilm Enhancement in Enterococcus faecalis. J Bacteriol 2005; 187:6213-6222.
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IssueVol 17 No 3 (2025) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijm.v17i3.18819
Keywords
Pseudomonas aeruginosa Pseudomonas infections Antibiotic resistance Biofilms

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How to Cite
1.
Abed HS, Hosseini SM, Mohammed Jassim Z. Immunological and molecular detection of biofilm formation and antibiotic resistance genes of Pseudomonas aeruginosa isolated from urinary tract. Iran J Microbiol. 2025;17(3):376-381.