Abstract
ABSTRACT
Aging populations face a growing burden of neurodegenerative disease and behavioral decline. The microbiota is increasingly implicated in host physiology, highlighting an urgent need to understand how gut microbes modulate brain function and late-life health. Here, we develop a high-throughput microbe–host screening platform to systematically dissect how bacterial genes shape organismal behavior. Using the
Escherichia coli
Keio library of 3,985 distinct non-essential single-gene deletion mutants in combination with
Caenorhabditis elegans
, we quantitatively profiled 768 behavioral features per bacterial clone and uncovered a coherent module of bacterial genes involved in iron homeostasis that robustly reprogrammed host behavior. Bacterial omics analyses revealed that alterations in iron homeostasis amplify siderophore production in a TCA cycle-dependent manner, and loss of enterobactin biosynthesis abolished the bacteria-induced changes in worm movement. Transcriptional, molecular and functional studies demonstrated that bacterial enterobactin activates host neuromuscular responses to shape both lifespan and healthspan in a manner dependent on the mitochondrial unfolded protein response. Thermal proteome profiling identified mitochondrial glutaryl-CoA dehydrogenase and the electron-transfer flavoproteins A and B as enterobactin-binding targets that control mitochondrial function. Finally, genetic manipulation of neuronal mitochondrial and cytosolic reactive oxygen species via superoxide dismutase and catalase revealed that redox state modulates enterobactin-driven changes in movement and lifespan through the secretin-family GPCR neuropeptide receptor PDFR-1. Together, these findings establish microbial enterobactin as a non-canonical neurotransmitter regulating neuronal mitochondrial function, behavior and aging, defining a gut bacteria–brain axis with broad implications for maintaining late-life health.