DOI: 10.1094/CC-82-0125 |  VIEW ARTICLE

Comparison of Endoproteinases of Various Grains.

Berne L. Jones (1,2) and George L. Lookhart (3). (1) USDA-ARS, Cereal Crops Research Unit, 501 N. Walnut St., Madison, WI 53726. Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may also be suitable. (2) Corresponding author. RR1, Box 6, Kooskia, ID 83539. Phone: 208-926-4429. E-mail: <bhjones@bmi.net> (3) USDA-ARS, Grain Marketing and Production Research Center, 1515 College Street, Manhattan, KS 66502. Cereal Chem. 82(2):125-130. Accepted November 15, 2004. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. American Association of Cereal Chemists, Inc., 2005.

Two-dimensional isoelectric focusing (IEF) × PAGE gels were used to compare the endoproteolytic (gelatinase) activities of germinated barley with those of bread and durum wheat, rye, triticale, oat, rice, buckwheat, and sorghum. Barley was used as the standard of comparison because its endoproteinase complement has been studied previously in the greatest detail. The characteristics of the grain proteases were appraised from their migration patterns and by how they were affected by pH levels. All of the germinated grains contained multiple enzyme activities and their separation patterns and pH levels were at least similar to those of barley. The proteinases of the bread and durum wheats, rye, oat, and sorghum were most similar to those of barley, whereas the other grains provided more varied patterns. The rice and buckwheat proteinases developed much more slowly than those of the other grains. The activity patterns of the triticale resembled those of the parents, wheat and rye, but the triticale contained many more activities and higher overall proteolytic activities than any of the other species. These results should be applied to scientific or commercial procedures with caution because grains contain potent endogenous proteinase inhibitors that could inactivate some of these enzymes in various tissues or germination stages.