Molecular Study of Urease ureR Gene of Proteus mirabilis Isolated from Urinary Tract Infections, Najaf, Iraq

Proteus mirabilis is considered one of the causative pathogens that leads to complicated urinary tract infection (UTI); moreover, it produces urease. Urease plays a key role as a virulence factor for P. mirabilis. UreR, a member of the AraC/XylS family of transcriptional regulators, positively activates the expression of the ure gene cluster in the presence of urea. Therefore, this study was designed to investigate the contribution of ureR to urease activity and virulence in urinary tract infections. A total of 74 clinical samples were collected from August to December 2020. The urine samples were taken from individuals with parasitic infections in their urinary tracts. After cultivating the samples on the MacConkey agar, the initial identification was performed based on traditional methods with the automated VITEK-2 compact method. Bacterial isolates were inoculated by stabbing and streaking into a slant of urease agar, which were then incubated at 37°C for 24-48 h. The polymerase chain reaction technique was used to detect the P. mirabilis ureR gene. The results of biochemical studies were utilized to confirm the identification of P. mirabilis isolates that had previously been made. All isolates had the same oxidase-negative, catalase-positive, oxidase-negative, and catalase-positive properties. They were motile, methyl red, and uric acid, catalase, citrate, and urease positive. The results of investigating the expression of the ureR gene in 15 isolates of P. mirabilis suggested that only 14 (93.3%) of the isolates produced ureR gene products using unique primers.