Photorhabdus is a member of the family Enterobacteriaceae that lives in a mutualistic association with a Heterorhabditis nematode worm. The nematode worm burrows into insect prey and regurgitates Photorhabdus, which goes on to kill the insect. The nematode feeds off the growing bacteria until the insect tissues are exhausted, whereupon they reassociate and leave the cadaver in search of new prey. This highly efficient partnership has been used for many years as a biological crop protection agent. The dual nature of Photorhabdus as a pathogen and mutualist makes it a superb model for understanding these apparently exclusive activities. Furthermore, recently identified clinical isolates of Photorhabdus are helping us to understand how human pathogens can emerge from the enormous reservoir of invertebrate pathogens in the environment. As Photorhabdus has never been found outside a host animal, its niche represents an entirely biotic landscape. In this review we discuss what molecular adaptations allow this bacterium to complete this fascinating and complex life cycle.

中文翻译：

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Photorhabdus 和许多宿主。

Photorhabdus 是肠杆菌科的一员，与异形线虫线虫共生。线虫蠕虫钻入昆虫猎物体内并反刍 Photorhabdus，后者继续杀死昆虫。线虫以生长的细菌为食，直到昆虫组织耗尽，然后它们重新结合并离开尸体寻找新的猎物。这种高效的合作伙伴关系已被用作生物作物保护剂多年。Photorhabdus 作为病原体和共生者的双重性质使其成为理解这些明显排他性活动的极好模型。此外，最近发现的 Photorhabdus 临床分离株正在帮助我们了解人类病原体如何从环境中巨大的无脊椎动物病原体库中出现。由于 Photorhabdus 从未在宿主动物之外被发现过，它的生态位代表了一个完全生物的景观。在这篇综述中，我们讨论了哪些分子适应性使这种细菌能够完成这个迷人而复杂的生命周期。