325-Structural Basis of Toxin Targeting by UmbA Lectins

Paper Talk · Dec 19, 2025 · 19m

The article examines the intricate mechanism used by umbrella toxins—complex antibacterial particles secreted by Streptomyces—for competition. This mechanism relies on UmbA lectin domains mediating species-specific binding to a novel cell surface carbohydrate receptor: the teichuronic acid-wall teichoic acid (TUA-WTA) hybrid. Resistance studies and cryo-electron microscopy (cryo-EM) confirmed that the toxin's lectin domain specifically recognizes the hypervariable TUA polymer, allowing target cell adhesion. The study concludes that the widespread genomic diversity observed in both the UmbA…