Glutenin

Glutenin is a group of seed storage proteins found in wheat that constitutes a major part of gluten. Along with gliadins, glutenin contributes to the viscoelastic properties of dough, enabling gas retention and loaf rise. Glutenin proteins form a network through interchain disulfide bonds, while gliadins provide more extensibility.

Glutenin consists of two main classes of subunits: high molecular weight glutenin subunits (HMW-GS) and low molecular weight glutenin subunits (LMW-GS). HMW-GS are encoded by Glu-1 loci on group 1 chromosomes and are among the larger glutenin components (about 80–90 kDa). LMW-GS are encoded by Glu-3 loci and are smaller (roughly 20–35 kDa).

These subunits assemble into large glutenin polymers via disulfide linkages, forming the elastic network that strengthens dough. The size and composition of the glutenin polymers influence dough strength, elasticity, and gas retention during fermentation. Breeders tune Glu-1 and Glu-3 alleles to optimize bread-making quality for different wheat varieties and products.

Glutenin, together with gliadin, makes up gluten in wheat endosperm. It is synthesized during grain development and stored in protein bodies within the endosperm. In susceptible individuals, gluten proteins can trigger adverse immune reactions, such as celiac disease, making glutenin a target for both nutrition and food safety considerations.