Regulatory effects and underlying mechanisms of glomalin-related soil protein on the environmental behavior of heavy metals

Abstract

Glomalin-related soil protein (GRSP), a widely distributed glycoprotein complex in soil, has a high potential for heavy metal pollution remediation due to its unique physicochemical properties and synergistic effects with plant roots. However, lack of comprehensive studies on regulatory mechanisms of GRSP in heavy metal pollution restricts its application in soil pollution risk management. This review synthesizes current knowledge on GRSP biosynthetic pathways, structural characteristics, and of heavy metal transport regulation in the soil-plant system using a multidisciplinary analysis of molecular biology, ecology, and environmental science. As a key biogeochemical regulator at the soil-plant interface, GRSP influences heavy metal speciation through various mechanisms. Its surface functional groups (e.g., carboxyl and hydroxyl) form stable coordination complexes with heavy metal ions, enhance soil particle aggregation, and restrain heavy metal bioavailability by modifying the physicochemical and biochemical properties of the rhizosphere soil. Collectively, these functions mitigate heavy metal phytotoxicity and enhance plant metabolic resilience. This review establishes a theoretical framework for sustainable environmental pollution management and ecological restoration by systematically elucidating GRSP sequestration capacity, bioavailability control, and environmental responsiveness, providing new insights and theoretical support for the development and application of green and efficient heavy metal-contaminated soil remediation technologies.