Article Search

Microbiology and Biotechnology Letters


Molecular and Cellular Microbiology  |  Functional Genomics and Systems Biology

Microbiol. Biotechnol. Lett.

Received: March 11, 2022; Revised: May 1, 2022; Accepted: May 3, 2022

Prevalence and cytotoxic effects of some colibactin and cnf genes among Escherichia coli isolated from urinary tract infections

Hiba A.S. Alhadidi1 , Safaa A. S. Al-Qaysi2*, and Mohammad M. F. Al-Halbosiy3

1Al-Esraa University College, Department of Dentistry, Baghdad, 10071, Iraq 2Department of Biology, College of Science for (Women), University of Baghdad, Baghdad, 10071 , Iraq 3 Biotechnology Research Center, Al-Nahrain University, Baghdad, 10072, Iraq

Correspondence to :
Safaa Al-Qaysi,


Colibactins (clb) and Cytotoxic Necrotizing Factors (cnf) are virulence factors that affect the cell cycle through cellular differentiation, proliferation, and apoptosis. Urinary tract infections (UTIs) are the most common among the outpatient infections, with a lifetime incidence of about 60-65% in adult female. This study is aimed to isolation of uropathogenic Escherichia coli (UPCE) from urine specimens and investigate the prevalence of cnf 1, 2 and clb A, B genes among these isolates. A total of 110 E. coli isolates were collected from patients with UTIs. All the isolates were examined for their hemolytic activity, only 46 isolates showed a halo zone of hemolysis on blood agar. The collected UPEC isolates were screened for the existence of cnf, clb A, B genes. The results revealed that 28 isolates out of 110 harbored the clbA gene, 40 isolates out of 110 harbored clb B, and 24 isolates harbored cnf1. 13 isolates were harbored clbA, clbB, and cnf1 genes, while no cnf2 gene was detected among isolates. The molecular detection revealed that 8 out of 28 hemolytic isolates carrying the clbA, 11out of 40 carrying clbB, 1out of 24 carrying cnf 1, 5 out of 9 carrying clbA+clbB. Finally, 7 out of 13 isolates were hemolytic and carrying clbA, clbB, and cnf1 genes. Further, to investigate the cytotoxicity of E. coli harbouring clb and cnf genes, exposure of REF as eukaryotic cells to E. coli producing colibactin induces DNA damages and causes leading to cell cycle arrest, senescence, and death.

Keywords: Colibactin, Uropathogenic, E. coli, cytotoxic effects

Starts of Metrics

Share this article on :

  • mail

Most KeyWord ?

What is Most Keyword?

  • It is most registrated keyword in articles at this journal during for 2 years.