FimH is a bacterial adhesin protein located at the tip of Escherichia coli fimbria that functions to adhere bacteria to host cells. Thus, FimH is a critical factor in bacterial infections such as urinary tract infections and is of interest in drug development. It is also involved in vaccine development and as a model for understanding shear-enhanced catch bond cell adhesion. To date, over 60 structures have been deposited in the Protein Data Bank showing interactions between FimH and mannose ligands, potential inhibitors, and other fimbrial proteins. In addition to providing insights about ligand recognition and fimbrial assembly, these structures provide insights into conformational changes in the two domains of FimH that are critical for its function. To gain further insights into these structural changes, we have superposed FimH's mannose binding lectin domain in all these structures and categorized the structures into five groups of lectin domain conformers using RMSD as a metric. Many structures also include the pilin domain, which anchors FimH to the fimbriae and regulates the conformation and function of the lectin domain. For these structures, we have also compared the relative orientations of the two domains. These structural analyses enhance our understanding of the conformational changes associated with FimH ligand binding and domain-domain interactions, including its catch bond behavior through allosteric action of force in bacterial adhesion.

中文翻译：

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对细菌蛋白FimH的结构进行RMSD分析可鉴定其凝集素结构域的五个构象。

FimH是一种细菌粘附素蛋白，位于大肠杆菌菌毛末端，可将细菌粘附到宿主细胞上。因此，FimH是细菌感染（例如尿路感染）中的关键因素，并且在药物开发中引起关注。它也参与疫苗的开发，并作为理解剪切增强的捕获键细胞粘附的模型。迄今为止，已经在蛋白质数据库中保存了60多个结构，显示出FimH和甘露糖配体，潜在抑制剂和其他纤维蛋白之间的相互作用。除了提供有关配体识别和纤维组装的见解之外，这些结构还提供了对FimH的两个域中对其功能至关重要的构象变化的见解。为了进一步了解这些结构性变化，我们叠加了FimH' 在所有这些结构中结合甘露糖结合的凝集素结构域，并使用RMSD作为度量标准，将结构分为五组凝集素结构域构象体。许多结构还包括菌毛蛋白结构域，其将FimH锚定在菌毛上并调节凝集素结构域的构象和功能。对于这些结构，我们还比较了两个域的相对方向。这些结构分析增强了我们对与FimH配体结合和域-域相互作用相关的构象变化的理解，包括其通过细菌粘附力的变构作用引起的捕获键行为。它将FimH锚定在菌毛上并调节凝集素结构域的构象和功能。对于这些结构，我们还比较了两个域的相对方向。这些结构分析增强了我们对与FimH配体结合和域-域相互作用相关的构象变化的理解，包括其通过细菌粘附力的变构作用引起的捕获键行为。它将FimH锚定在菌毛上并调节凝集素结构域的构象和功能。对于这些结构，我们还比较了两个域的相对方向。这些结构分析增强了我们对与FimH配体结合和域-域相互作用相关的构象变化的理解，包括其通过细菌粘附力的变构作用引起的捕获键行为。