Barley seed as a production host for industrially important proteins

Barley is one of the most important cereal crops worldwide. Barley cultivars have been developed to store large amounts of carbohydrates, oil and protein in the endosperm. The processing quality of barley can be modified by altering the structural grain constituents (starch, proteins, lipids, cell walls) or the enzyme activities that mobilise storage reserves in the seed. The first gene transfers to barley aiming at commercial applications, e.g. improvement of malting and feed quality, have been published in recent years. These studies have clearly demonstrated the concept that active, heterologous enzymes can be produced in transgenic barley grains, thus indicating that the barley seed is a suitable host for recombinant protein production. Expression of various proteins, e.g. enzymes and different types of therapeutic proteins, holds great promise for the generation of novel, value-added barley varieties in the future.