Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
J Med Microbiol. 2023 Feb;72(2). doi: 10.1099/jmm.0.001660.
. The main aetiological agent of urinary tract infection (UTI) is , categorized as uropathogenic (UPEC). The genome of UPEC shows a high degree of plasticity, which leads to the emergence of 'intermediary strains' with different traits from the parental pathotypes.. We aimed to assess the frequency and types of the hybrid UPEC among isolates causing UTI and characterize virulence properties of these hybrid isolates molecularly and phenotypically.. After detection of intestinal pathogenic (IPEC) virulence markers among 200 UPEC isolates, they were assessed for the presence of 40 virulence genes (VGs) of extraintestinal, uropathogenic and diarrhoeagenic , phylogenetic group typing, phenotypic traits including biofilm formation, adherence and invasion to HeLa cells, haemolysis activity and antimicrobial resistance.. The analysis showed 21 (10.5 %) UPEC isolates carried enteroaggregative (EAEC) and enteropathogenic (EPEC) virulence markers. Twenty isolates carried the (EAEC) and one the and genes (EPEC), which were classified as hybrid strains. The most commonly identified genes were (71.5 %), (66.7 %), (62 %), (57.1) and (47.6 %). Biofilm production, adhesion and invasion were found among 17 (81), 18 (85.7) and 11 (52.4 %) hybrids, respectively. Investigation of the genetic characteristics, phylogenetic group and virulence profile of the detected hybrids revealed that they have genetic diversity and do not belong to a particular clonal lineage.. The present study reveals that some UPEC may carry virulence markers of IPEC pathotypes. EAEC and EPEC seem to have a greater tendency to form hybrids and cause UTI. Further studies are needed to elucidate what factors contributed to survival in the urinary tract system and facilitate infection and whether these combinations lead to an increase in pathogenicity or not.
. 尿路感染（UTI）的主要病原体是尿致病性大肠杆菌（UPEC）。UPEC 的基因组具有高度的可塑性，导致出现具有与亲本病原体不同特征的“中间菌株”。. 我们旨在评估引起 UTI 的 UPEC 分离株中杂交 UPEC 的频率和类型，并从分子和表型上表征这些杂交分离株的毒力特性。. 在检测到 200 株 UPEC 分离株中的肠道致病性（IPEC）毒力标志物后，评估它们是否存在 40 种肠外、尿致病性和腹泻性的毒力基因（VGs）、进化群分型、表型特征，包括生物膜形成、对 HeLa 细胞的黏附和侵袭、溶血活性和抗菌药物耐药性。. 分析显示 21 株（10.5%）UPEC 分离株携带肠聚集性大肠杆菌（EAEC）和肠致病性大肠杆菌（EPEC）毒力标志物。20 株携带（EAEC）和 1 株携带（EPEC）和（EHEC）基因，被归类为杂交株。最常见的鉴定基因是（71.5%）、（66.7%）、（62%）、（57.1%）和（47.6%）。生物膜生成、黏附和侵袭分别在 17 株（81%）、18 株（85.7%）和 11 株（52.4%）杂交株中发现。对检测到的杂交株的遗传特征、进化群和毒力谱的调查表明，它们具有遗传多样性，不属于特定的克隆谱系。. 本研究表明，一些 UPEC 可能携带 IPEC 病原体的毒力标志物。EAEC 和 EPEC 似乎更有可能形成杂交株并引起 UTI。需要进一步的研究来阐明是什么因素导致它们在泌尿系统中存活并促进感染，以及这些组合是否会导致毒力增加。
