Review of glomalin-related soil protein and its environmental function in the rhizosphere

Glomalin (or glomalin-related soil protein) is thought to be produced by arbuscular mycorrhizal fungi. It is a thermotolerant glycoprotein that contains metal ions and has special physical and chemical characteristics. The structure and function of glomalin have been intensively studied. We review progress in the characterization and properties of glomalin as well as its environmental functions in the rhizosphere (especially its chelation of heavy metals). Research has shown that glomalin is a putative homolog of heat shock protein 60 and can carry different metal ions because of different kinds of soil. Further research on methods for its measurement is urgently needed.