Speaker
Description
Necrosis- and ethylene-inducing peptide 1-like proteins (NLPs) are a large family of microbial toxins secreted by taxonomically diverse pathogens—including bacteria, fungi, and oomycetes—that infect a wide range of crops such as potato, tomato, soybean, and grapevine. These pathogens significantly burden global agriculture. A sad example is Phytophthora infestans, an NLP-producing oomycete that caused the Great Irish Famine. NLPs interacts with plant membranes through glycosylinositol phosphorylceramides (GIPCs), but the specificity of these interactions and the mechanism of toxicity remain unclear. We used microfluidic assays on giant unilamellar vesicles (GUVs) to study NLP binding and pore formation in GIPC-containing membranes (Pirc et al., 2022; Žibrat et al., 2025). Binding of diverse cytotoxic NLPs was observed on membranes containing GIPCs from monocots or dicots, but not on control POPC membranes with or without sterols. The microfluidic setup allowed precise monitoring of binding dynamics and subsequent vesicle leakage, revealing a time lag between NLP binding and leakage. Corroborated by other approaches—including conductance measurements across planar lipid bilayers, high-speed AFM, and MD simulations—these results show that NLPs form transient pores without penetrating the membrane, which is in stark contrast to pore-forming toxins such as lysenin.
Pirc et al. (2022). An oomycete NLP cytolysin forms transient small pores in lipid membranes. Science Advances, 8(10), eabj9406.
Žibrat Kalanj et al. (2025). Surface plasticity of the cytotoxic Nep1-like protein enables promiscuity in binding to its lipid receptor glycosylinositol phosphorylceramides. Science Advances, 11(41), eadw6401.