srjmsSRJMSSRJMS2788-9483https://doi.org/10.47310/iarjcmb.2023.v03i02.004The Role of Haemolysin in Pathogenesis of Escherichia coli, Proteus mirabilis and P. aeruginosa Bacteria that Cause Urinary Tract Infections in Pregnant and Non-Pregnant WomenHananMohammedHussienJasimHusseinMakhrmashDepartment of Medical Microbiology, College of Medicine, University of Wasit, Wasit, IraqBackground: Urinary tract infection (UTIs) is one of the most common infections afflicting women. Hemolysins or haemolysins was a potential virulence factor produced by microorganisms (M.O). Probiotic refer to harmless live normal flora M.O, which are mostly strains of Lactobacillus spp., Bifidobacterium spp., and others. These microorganisms help the host's health when given in the right dosages. Aims: To identify gram -ve bacterial species isolated from urinary tract infections, and also to evaluate in-vitro the antimicrobial activity of antibiotic and also to evaluate in-vitro the antimicrobial activity of selected probiotic species and antibiotic against some pathogenic bacteria, and hemolysin gene detection. Methods: A total 200 urine specimens were collected from patients with UTIs, that include pregnant (n = 100, 50%), non-pregnant (n = 100, 50%). Bacterial colonies were Gram stained and microscopically examined. Biochemical tests were done to identify pathogen species. The Kirby-Bauer disk diffusion method was used for antibiotic testing.The well diffusion method and agar spot method was used for detection probiotic affectivity to a group of bacteria isolated and Detection of some virulence genes of bacterial isolates by PCR. Results: The result of identification revealed that the number of patients were with significant bacteriuria among 200 urine specimens with positive culture was 60% and The UPEC was presented (26.7%) of samples culture, P. aeruginosa 5.8% and P. mirabilis 3.3%. Diagnosis using PCR of 16S rRNA of isolates was 100% positive for all isolates. The E. coli isolates was 100% for both Hly-A and Hly-B gene, P. aeruginosa Hly-1 (plcH) and Hly-2 (exlA) were 85.7% and 71.4% respectively; whereas, P. mirabilis Hly-A (hmpA) and Hly-B (hmpB) were 50% and 75%, respectively. The UPEC and P. mirabilis isolates show higher resistance level of the present study for lincomycin, Rifampin, Amoxicillin-clavulanate, colistin and Nalidixic acid were 100%, while the P. mirabilis were most resistant to colistin, Nalidixic acid and Amoxicillin-clavulanate were 100%. In susceptibility testing using well diffusion method, L. acidophilus had effect against 77% (p = 0.008) and L.Plantarium had coverage against (90%) (p = 0.003). Lactobacillus acido and L. Plantarum 95%, while in agar spot method, L. acidophilus had effect against 82% and L. plantarium had coverage against 95%, and L. acido and L. plantarum was 100%. Conclusion: most isolates was resistant to colistin Nalidixic acid and Azithromycin, This investigation showed Hly-A and Hly-B are a gene found in bacterial cells that allows them to be resistant to antibiotics.This study indicates the antibacterial efficacy properties of Lactobacillus spp., to inhibit the growth in-vitro of pathogenic bacteria but probiotic cannot inhibit strong biofilm formation for all isolates.