Abstract
Thiamin-binding proteins from plant seeds are interesting storage proteins because they have dual functions: retention of thiamin in dormant seeds and provision of a nitrogen source at germination. The thiamin-binding proteins differ in molecular mass, subunit structure, amino acid composition, optimum pH for thiamin-binding activity, and binding affinity for thiamin and thiamin analogs. However, they all specifically bind free thiamin but not thiamin phosphates, which is a characteristic property of thiamin-binding proteins from plant seeds, and have a common mechanism of thiamin binding. This information suggests that the nutritive quality of seeds might be improved by using genetic engineering techniques with the genes producing thiamin-binding proteins.
