VARIABILITY IN ANTIFUNGAL PROTEINS IN THE GRAINS OF MAIZE, SORGHUM AND WHEAT

Crude protein extracts were made from kernels of 12 cultivars each of maize, sorghum and wheat. These preparations were fractionated on sodi um dodecyl sulfate (SDS)-polyacrylamide gels and subjected to Western blot analyses. Bands corresponding to chitinases and beta-glucanases w ere identified immunologically (Western blots) and on activity gels. R ibosome Inactivating Protein(s) (RIP) and permatins were identified im munologically. In maize, two chitinase bands (25-29 kDa) were seen in all cultivars, and a third band of about 23 kDa was detected in 7 of t he 12 cultivars. Two or three beta-glucanase bands of sizes between 24 and 36 kDa (probably a mixture of 1,3-beta- and 1,3-1,4-beta-glucanas es) were detected in blots of SDS gels, and one band was detected in a ctivity gels (1,3-beta-glucanase). In sorghum, one chitinase band of a pproximately 29 kDa, and two or three additional bands ranging in size from 21-24 kDa were observed. Only one beta-glucanase band was identi fied, with an estimated molecular weight of 30 kDa. All bands that app eared on Western blots of SDS gels corresponded to bands detected on a ctivity gels. In wheat, one chitinase band of around 20 kDa, one beta- glucanase band of about 30 kDa and one RIP band of about 30 kDa were i dentified. Permatins (molecular weight about 22 kDa) were identified i n maize, sorghum and wheat, with the different cultivars having varyin g amounts of permatins.