Purification and Characterization of Calmodulins from Papaver somniferum and Euphorbia lathyris

Abstract

Calmodulins (CaM) were isolated and characterized from two well-known latex producing plants, Papaver somniferum and Euphorbia lathyris. The molecular weights of both were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be 17,000 comparable to that of bovine brain CaM. Amino acid compositions also compared similarly with those of known CaMs, with regard to the presence of trimethyllysine and the ratio of phenylalanine to tyrosine. The Cornish-Bowden equation (SAn) revealed strong statistical correlations of P. somniferum and E. Iathyris CaM with those of other plants and animals, although their amino acid compositions were not identical. Both plant CaM stimulated CaM dependent cAMP phosphodiesterase: for Papaver somniferum the K. was found to be 1.09 nanomolar and for Euphorbia lathyris, 2.01 nanomolar.

Purification and characterization of calmodulin from cultured cells of catharanthus roseus

“…Calmodulins from a few other sources have also been found to contain higher amounts of proline. For example, the purified protein from the leaves of Papaver somniferum and Euphorbia lathyris (Thompson et al, 1989) contain 5 and 4 residues of proline respectively (Table 2). In addition, 10 residues of proline were detected in CM isolated from Russufa sp., a Basidiomycete (Grand et a f .…”

Purification of calmodulin from rice bran and activation of glutamate decarboxylase by Ca2+/calmodulin

“…The amino acid composition of rice bran CaM was presented in Table 2, along with several CaMs isolated from plant sources 20, 22, 30, 31. The protein had essentially similar composition as that reported for spinach leaf20 and was also very similar to that of other higher plants. It had a high percentage of aspartate (24 residues) and glutamate (27 residues), a single tyrosine, histidine and trimethyllysine, respectively, and the absence of tryptophan.…”

“…CaM is a small, highly conserved protein, and has been isolated and characterised from several higher plants including Catharanthus roseus ,16 Pharbitis nil ,18 Citrus sinensis ,19 Papaver somniferum ,20 Euphorbia lathyris ,20 oat,21 barley22 and spinach 23. These proteins share many structural and functional features with CaMs from animal tissues and yeast, since similar molecular weight, mobility performance, amino acid composition and ability to stimulate phosphodiesterase were found in these CaMs.…”

Interactive Effects of PEG-induced Water Stress and CaCl2 on the Status of Calcium and Ca2+ Binding Proteins During Seedling Growth of Peanut (Arachis hypogaea L.) Cultivars

“…The protein concentration was determined using the Bradford reagent (Bradford, 1976). Amino acid analysis of hydrolysed CaM at 110 C was performed following the method of Thompson et al (1989) with an automatic amino acid analyser. Isolated and purified CaM activity was tested by studying its ability to stimulate cAMP phosphodiesterase.…”