A Comparative Investigation of Peroxidases from Germinating Peanuts (Arachis hypogaea): Electrophoresis

Abstract

Dormant seed and organs of 0-, 1-, 2-, 5-, 8-, 11-, and 14-day-old plants of Arachis hypogaea L. were homogenized in phosphate buffer and the lipid-free extracts analyzed for benzidine and pyrogallol peroxidases using starch-gel electrophoresis. On a wet weight basis, one weak band of benzidine peroxidase activity was detected in dormant cotyledons and three bands in 1-day cotyledons. In 5-day tissue, activity had increased significantly; at 14 days, the number of bands had decreased but staining intensity was maintained. In the extract from dormant axis, a single cathodic site of benzidine peroxidase activity was observed; however, on day two there was a marked increase in the number of bands and intensity of reaction in epicotyl and hypocotylradicle tissues. By day 14, the number and density of bands had decreased noticeably in the epicotyl and hypocotyl. Extracts from 14-day roots exhibited more sites of reaction and greater intensity of staining of benzidine peroxidase than at five days of growth. Localized areas of activity at Rf -0.44 and -0.52 were present in extracts of all four organs when either benzidine or pyrogallol was used as the hydrogen donor. Although marked similarity existed between banding patterns of organs, qualitative and quantitative ontogenetic differences in peroxidases were apparent.