Phages Mediate Bacterial Self-Recognition

Cells are social, and self-recognition is an important and conserved aspect of group behavior where cells assist kin and antagonize non-kin to conduct group behavior such as foraging for food and biofilm formation. However, the role of the common bacterial cohabitant, phage, in kin recognition, has not been explored. Here we find that a boundary (demarcation line) is formed between different swimming Escherichia coli strains but not between identical clones; hence, motile bacterial cells discriminate between self and non-self. The basis for this self-recognition is a novel, 49 kb, T1-type, lytic phage of the family siphoviridae (named here SW1) that controls formation of the demarcation line by utilizing one of the host’s cryptic prophage proteins, YfdM, to propagate

细胞具有社会性，而自我识别是群体行为中一项重要且保守的特征：细胞会协助亲缘个体、对抗非亲缘个体，以完成觅食、生物膜形成等群体行为。然而，作为细菌常见共生体的噬菌体（phage）在亲缘识别中所发挥的作用，迄今尚未得到探索。本研究发现，不同游动型大肠杆菌（Escherichia coli）菌株之间会形成边界（分界划线），而同克隆菌株之间则不会出现该现象；因此，具有运动能力的细菌细胞能够区分自我与非自我。本次自我识别的分子基础为一种新型、长度49kb的T1型裂解性长尾噬菌体科（Siphoviridae）噬菌体（本研究将其命名为SW1）：该噬菌体通过利用宿主的一种隐性前噬菌体蛋白YfdM完成增殖，进而调控分界划线的形成。