Isolation and partial characterization of fractions with ribonuclease activity from latex of Calotropis procera (Aiton) W.T. Aiton and Pedilanthus tithymaloides (L.) Poit

Abstract

In order to isolate and characterize partially ribonucleases (RNases) enzymes contained in the latex from Calotropis procera and Pedilanthus tithymaloides, samples were collected from mature plants. Soluble proteins were extracted with sodium acetate and centrifugation at 16,000 xg for 15 min and fractionated by ion exchange chromatography. Molecular mass was estimated by linear regression equations. Glycosylation tests were conducted. In both species, proteins with RNase activity showed a molecular mass between 28 and 30 kDa. No evidence of glycosylated proteins in latex from C. procera. In P. tithymaloides, RNase may be a glycosylated protein.