Julian H. Lewis

An immunological and chemical study of the alcohol-soluble proteins of cereals.

The prolamines, or alcohol-soluble proteins, are the characteristic proteins of cereal grains. These proteins were isolated from wheat, Triticum vulgare, durum, Triticum durum, emmer, Triticum dicoccum, spelt, Triticum spelta, einkorn, Triticum monococcum, rye, Secale cereale, oats, Avena sativa, barley, Hordeum vulgare, corn, Zea mays, kafir, Andropogon sorghum, teosinte, Euchlaena mexicana Schrad., and sorghum, Sorghum vulgare, and subjected to chemical and immunological study. The chemical study included the nitrogen distribution by the Van Slyke method, the free amino nitrogen, the free carboxyl groups, the true ammonia nitrogen, the cystine and tryptophane content, and the acid and alkali binding at various hydrogen ion concentrations and at different temperatures. This study showed certain similarities of chemical composition among the prolamines, as a class, as contrasted with the composition and behavior of such proteins as casein and fibrin. The chemical evidence suggested that the prolamines studied might be grouped into a “wheat group”, which would include the proteins isolated from the genus Triticum, and a “corn group” including those isolated from maize, teosinte, kafir, and sorghum. The genetic behavior of these groups has been extensively studied by plant blreeders, although relatively more work has been done upon the wheat group. Sakamura, 1 Kihara, 2 and Sax 3 have shown that T. monoccum is characterized by having 7 chromosomes, that T. dicoccum and T. durum have 14 chromosomes, and T. vulgare and T . spelta have 21 chromosomes.