A Bacterial Pathogen Senses Host Mannose to Coordinate Virulence

• Published in: iScience
• Main Authors: Lifan Wei, Haoxian Qiao, Brandon Sit, Kaiyu Yin, Guanhua Yang, Ruiqing Ma, Jiabao Ma, Chun Yang, Jun Yao, Yue Ma, Jingfan Xiao, Xiaohong Liu, Yuanxing Zhang, Matthew K. Waldor, Qiyao Wang
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2019
• Subjects: Science; Q; Scophthalmus maximus; Turbot
• Online Access: https://doi.org/10.1016/j.isci.2019.09.028; https://doaj.org/article/4e28e5b39aac459eae1a20694fae6f5d

Summary: Bacterial pathogens are thought to activate expression of virulence genes upon detection of host-associated cues, but identification of the nature of such signals has proved difficult. We generated a genome-scale defined transposon mutant library in Edwardsiella piscicida, an important fish pathogen, to quantify the fitness of insertion mutants for intracellular growth in macrophages and in turbot (Scophthalmus maximus). These screens identified EvrA, a transcription activator that induces expression of esrB, a key virulence regulator. EvrA is directly bound and activated by mannose-6-phosphate (man-6P) derived from actively imported mannose. Mutants lacking EvrA or expressing an EvrA unable to bind man-6P were similarly attenuated in turbot. Exogenously added mannose promoted E. piscicida virulence, and high levels of mannose were detected in fish tissue. Together, these observations reveal that binding of a host-derived sugar to a transcription factor can facilitate pathogen sensing of the host environment and trigger virulence programs. : Pathogenic Organism; Microbiology; Fish Culture Subject Areas: Pathogenic Organism, Microbiology, Fish Culture