中文摘要：噬菌体广泛用作食品中的生物防治剂及食品生产工厂表面处理的抗菌剂。这种噬菌体的一个重要特征是对特定致病物种具有广泛的侵染性。噬菌体通过受体结合蛋白（RBPs）即尾纤维或尾刺（TSPs）附着在细菌细胞表面。RBPs的结合范围是噬菌体宿主范围和侵染性的主要决定因素，因此决定了噬菌体作为抗菌剂的适用性。噬菌体EP75和EP335广泛感染大肠杆菌血清型O157。为了更好地理解这两种噬菌体对宿主的识别，本文重点介绍了它们的RBP的结构和功能。本研究从短尾病毒EP335的基因组中鉴定出两种不同的尾部纤维：gp12和gp13，并利用荧光显微镜揭示了gp13如何识别大肠杆菌血清型O157和O26。噬菌体EP75属于Ackermannviridae科的kattervirus属，具有这类噬菌体普遍存在的四个TSP复合体(TSP 1-4)。本研究证明TSP1（gp167）和TSP2（gp168）分别对大肠杆菌O18A和O157 O-抗原的酶活性，以及TSP3（gp169.1）对O4、O7和O9沙门氏菌O-抗原的活性。EP75的TSPs与大肠杆菌噬菌体CBA120(TSP2)和HK620(TSP1)及沙门氏菌肌尾病毒Det7(TSP3)具有很高的相似之处，可以解释EP75的跨属侵染性。
外文摘要：Bacteriophages (phages) are widely used as biocontrol agents in food and as antibacterial agents for treatment of food production plant surfaces. An important feature of such phages is broad infectivity towards a given pathogenic species. Phages attach to the surfaces of bacterial cells using receptor binding proteins (RBPs), namely tail fibers or tailspikes (TSPs). The binding range of RBPs is the primary determinant of phage host range and infectivity, and therefore dictates a phage's suitability as an antibacterial agent. Phages EP75 and EP335 broadly infect strains of E. coli serotype O157. To better understand host recognition by both phages, here we focused on characterizing the structures and functions of their RBPs. We identified two distinct tail fibers in the genome of the podovirus EP335: gp12 and gp13. Using fluo-rescence microscopy, we reveal how gp13 recognizes strains of E. coli serotypes O157 and O26. Phage EP75 belongs to the Kuttervirus genus within the Ackermannviridae family and features a four TSP complex (TSPs 1-4) that is universal among such phages. We demonstrate enzymatic activity of TSP1 (gp167) and TSP2 (gp168) toward the O18A and O157 O-antigens of E. coli, respectively, as well as TSP3 activity (gp169.1) against O4, O7, and O9 Salmonella O-antigens. TSPs of EP75 present high similarity to TSPs from E. coli phages CBA120 (TSP2) and HK620 (TSP1) and Salmonella myovirus Det7 (TSP3), which helps explain the cross-genus infectivity observed for EP75.
外文关键词：Bacteriophage；STEC；Escherichia coli O157；Salmonella；Tail fiber；Tailspike；Receptor binding protein；Lipopolysaccharide；O-antigen
作者：Witte, S；Zinsli, LV；Gonzalez-Serrano, R；Matter, CI；Loessner, MJ；van Mierlo, JT；Dunne, M
作者单位：Micreos Food Safety BV；Swiss Fed Inst Technol；Univ Miguel Hernandez
期刊名称：COMPUTATIONAL AND STRUCTURAL BIOTECHNOLOGY JOURNAL
期刊影响因子：6.018
出版年份：2021
出版刊次：19
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