Identification of γ‐type hordeins in barley

The barley mutant Risϕ 56 has a deletion of at least 85 kb of DNA at the Hor 2 locus, resulting in the absence from the seeds of almost all of the major B hordein group of storage proteins. We have purified two fractions containing the three remaining ‘B hordein‐like’ bands and determined their N‐terminal amino acid sequences. One fraction, containing the two bands with higher M r, gave a single major N‐terminal sequence which was closely related to those reported for γ‐type prolamins of wheat and rye. The sequence of the third band was also homologous with those of the γ‐type prolamins, but less closely so. We consider that the γ‐type prolamins are most closely related to the ancestral S‐rich prolamins of the Triticeae, and this is the first report of their presence in barley.