▎ 摘　　要

Despite the studies worldwide, the prevalence of ES beta L E. coli in the Iraq is still unknown. Realization of the demographic characterization of ES beta L E. coli infections will assist the prevention efforts. This study aimed to isolate clinical E. coli, determine their antimicrobial susceptibility, phenotypic and genotypic detection of ES beta L-producing ability, detection of some virulence-related genes, estimate the impact of graphene nano-sheets as antibacterial, and study the adherence-related gene expressions in E. coli isolates. Graphene nano-sheets were synthesized and characterized using XRD, UV, TEM, and SEM. E. coli isolates were identified using 16S rRNA. Antibiotic resistance was detected, virulence genes (blaTEM, blaSHV, BlaCTX-M-15, papC, and fimH) were screened using PCR. The antibacterial activity of graphene nano-sheets was screened using well-diffusion assay and MIC. The gene expression of adherence genes after treatment with graphene nano-sheets was evaluated using QRT-PCR. From a total of 512 identified using 16S rRNA, 359 (69.9%) were ES beta L-producing E. coli. The ES beta L genotypes positive were 83.56% (300/359) of E. coli isolates with the frequencies: 85% for blaCTX-M gene, 26% for blaSHV gene, and 28% for blaTEM gene. Graphene nano-sheets showed effective antibacterial activity with MIC 25 mu g/ml. Furthermore, graphene nano-sheets reduced the expression of papC, and fimH genes. This study has helped us to better understand the characteristics of ES beta L E. coli, their adherence gene harboring, and the potential ability of graphene nano-sheets to reduce bacterial growth, and the expression of adherence genes. Furthermore, the current study showed further step to understand the mechanisms by which graphene nano-sheets can conflict bacterial virulence and resistance.