Prolamins are a group of plantstorage proteins having a highproline amino acid content. They are found in plants, mainly in the seeds of cereal grains such aswheat (gliadin),barley (hordein),rye (secalin),corn (zein),sorghum (kafirin), andoats (avenin). They are characterised by a highglutamine andproline content, and have poor solubility in water. They solubilise best in strong alcohol (70–80%), light acid, and alkaline solutions. The prolamins of the tribe Triticeae, such as wheatgliadin, and related proteins (seeTriticeae glutens) are known to triggercoeliac disease, an autoimmune condition, in genetically predisposed individuals.[1]
Maize and sorghum prolamins are sorted by molecular weight into four classes, α, β, γ and δ. Alpha- and delta- prolamins cluster in a broad phylogenetic group (Group 1). The rest cluster into Group 2. Group 1 is widely duplicated in the two plants.[2] A database of Triticeae prolamins (glutens) is available.[3] There does not seem to be an analysis that tries to cluster both sources of prolamins into a grand classification.[citation needed]
