Fungal Siderophore Chemistry: High-Affinity Iron Chelation for Bioweathering and Nutrient Acquisition Siderophores (from Greek: “iron carriers”) are small, water-soluble, low-molecular-weight compounds (<1,000 Da) produced by bacteria, fungi, and some plants under iron-limiting conditions. They bind Fe³⁺ with extremely high affinity (stability constants often log K = 20–52), solubilizing otherwise insoluble iron from minerals and making […]