glomalin

Glomalin is a glycoprotein produced by arbuscular mycorrhizal fungi (AMF). The name derives from the Glomus genus, a group of AMF that colonize plant roots. Glomalin is released by fungal hyphae and spores and tends to accumulate in the soil, where it associates with organic matter and mineral particles.

It is believed to play a key role in soil aggregation by acting as a biological glue that binds particles into larger, more stable aggregates. This contributes to soil structure, porosity, water infiltration, and resistance to erosion, and it also helps protect soil organic carbon by stabilizing it within aggregates.

In soil science, a related concept is glomalin-related soil protein (GRSP), a proxy measurement used to estimate AMF activity and soil health. GRSP is typically extracted with heat and chemical buffers; it is not a single purified protein but a fraction of glycosylated AMF-derived material with varying forms and molecular weights.

Research on glomalin continues to refine its molecular identity and turnover, and its sensitivity to land management. Practices that support AMF, such as reduced tillage and plant diversity, can influence GRSP levels and soil aggregation, potentially affecting carbon storage and soil resilience.