大肠杆菌是尿路感染(UTI)的主要原因。虽然从动物中回收的特定克隆的基因组比较,人类肠外感染表现出高度的同一性,缺乏证明泌尿致病性的研究。在这项研究中,比较基因组学结合膀胱细胞和生物膜形成测定,对31种不同来源的大肠杆菌进行了检测:7种来自肉类(家禽,牛肉,和猪肉);2来自鸟类农场环境;12来自人类简单的UTI,uUTI;10来自人类复杂的UTI,cUTI.这些分离株是根据其遗传尿路致病性(UPEC)状态和系统发育背景选择的。计算机模拟分析显示相似的毒力基因谱,鞭毛,1型和毛毛,外膜蛋白(agn43,ompT,iha),和铁摄取(IutA,entA,和fyuA)相关性状是最普遍的(>65%)。在膀胱细胞检测中,中等到强的关联值(83%,60%,77.8%)和入侵(0%,70%,55.5%)由uUTI展示,cUTI,和动物分离株,分别。感兴趣的,uUTI分离株的侵袭能力明显低于cUTI分离株(p<0.05)。除一种外,所有分离物产生可测量的生物膜。值得注意的是,1个火鸡肉分离株O11:H6-F-ST457和2个cUTI大流行谱系O83:H42-F-ST1485-CC648和O25b:H4-B2-ST131,显示出很强的相关性,入侵和生物膜形成。这些分离株显示出1型菌毛和csg操纵子的共同携带,毒素(hlyF,tsh),铁吸收系统(IutA,entA,iroN),colicins,protectins(cvaC,ISS,kpsM,traT),ompT,还有malx.总之,在某些动物来源的大肠杆菌克隆中发现的类似的体外行为将进一步加强产生食物的动物作为UPEC的潜在来源的作用。膀胱细胞感染试验,结合基因组学,可能是评估尿路致病性的体内毒力模型的替代方法。
Escherichia coli is the main cause of urinary tract infections (UTI). While genomic comparison of specific clones recovered from animals, and human extraintestinal infections show high identity, studies demonstrating the uropathogenicity are lacking. In this study, comparative genomics combined with bladder-cell and biofilm formation assays, were performed for 31 E. coli of different origins: 7 from meat (poultry, beef, and pork); 2 from avian-farm environment; 12 from human uncomplicated UTI, uUTI; and 10 from human complicated UTI, cUTI. These isolates were selected based on their genetic uropathogenic (UPEC) status and phylogenetic background. In silico analysis revealed similar virulence-gene profiles, with flagella, type 1 and curli fimbriae, outer-membrane proteins (agn43, ompT, iha), and iron-uptake (iutA, entA, and fyuA) associated-traits as the most prevalent (>65%). In bladder-cell assays, moderate to strong values of association (83%, 60%, 77.8%) and invasion (0%, 70%, 55.5%) were exhibited by uUTI, cUTI, and animal-derived isolates, respectively. Of interest, uUTI isolates exhibited a significantly lower invasive capacity than cUTI isolates (p < 0.05). All isolates but one produced measurable biofilm. Notably, 1 turkey meat isolate O11:H6-F-ST457, and 2 cUTI isolates of the pandemic lineages O83:H42-F-ST1485-CC648 and O25b:H4-B2-ST131, showed strong association, invasion and biofilm formation. These isolates showed common carriage of type 1 fimbriae and csg operons, toxins (hlyF, tsh), iron uptake systems (iutA, entA, iroN), colicins, protectins (cvaC, iss, kpsM, traT), ompT, and malX. In summary, the similar in vitro behaviour found here for certain E. coli clones of animal origin would further reinforce the role of food-producing animals as a potential source of UPEC. Bladder-cell infection assays, combined with genomics, might be an alternative to in vivo virulence models to assess uropathogenicity.