This review explores the diverse world of beneficial bacterial symbioses in insects, highlighting how these partnerships contribute to insect fitness through nutrition, defense, and more. It examines the metabolic capabilities of these symbionts and the evolutionary pathways that have led to these host-beneficial relationships, noting the different origins of extracellular and intracellular symbionts. The authors discuss the mechanisms of symbiont establishment and transmission, as well as the impact of these associations on insect ecology and evolution. The article concludes by emphasizing the need for further research, particularly in experimentally tractable systems and within natural contexts, to fully understand the intricacies of insect-bacteria symbioses.
nature reviews microbiology https://doi.org/10.1038/s41579-025-01164-z
