As the most abundant microbes on Earth, novel bacteriophages (phages; bacteria-specific viruses) are readily isolated from environmental samples. However, it remains challenging to characterize phage–bacteria interactions, such as the host receptor(s) phages bind to initiate infection. Here, we tested whether transposon insertion sequencing (INSeq) could be used to identify bacterial genes involved in phage binding. As proof of concept, results showed that INSeq screens successfully identified genes encoding known receptors for previously characterized viruses of Escherichia coli (phages T6, T2, T4, and T7). INSeq screens were then used to identify genes involved during infection of six newly isolated coliphages. Results showed that candidate receptors could be successfully identified for the majority (five of six) of the phages; furthermore, genes encoding the phage receptor(s) were the top hit(s) in the analyses of the successful screens. INSeq screens provide a generally useful method for high-throughput discovery of phage receptors. We discuss limitations of our approach when examining uncharacterized phages, as well as usefulness of the method for exploring the evolution of broad versus narrow use of cellular receptors among phages in the biosphere.

作为地球上最丰富的微生物，新型噬菌体（噬菌体；细菌特异性病毒）很容易从环境样本中分离出来。然而，表征噬菌体-细菌相互作用仍然具有挑战性，例如宿主受体噬菌体结合以引发感染。在这里，我们测试了转座子插入测序（INSeq）是否可用于鉴定参与噬菌体结合的细菌基因。作为概念证明，结果表明 INSeq 筛选成功识别了编码先前鉴定的大肠杆菌病毒（噬菌体 T6、T2、T4 和 T7）的已知受体的基因。然后使用 INSeq 筛选来鉴定六种新分离的大肠杆菌噬菌体感染过程中涉及的基因。结果表明，大多数（六个中的五个）噬菌体的候选受体可以被成功识别；此外，编码噬菌体受体的基因是成功筛选分析中的热门基因。 INSeq 筛选为噬菌体受体的高通量发现提供了一种普遍有用的方法。我们讨论了我们的方法在检查未表征的噬菌体时的局限性，以及该方法在探索生物圈中噬菌体之间细胞受体的广泛与狭义使用的演变的有用性。