Purification and biochemical characterization of a highly active cysteine protease ervatamin A from the latex of Ervatamia coronaria.

摘要: Ervatamia coronaria, a flowering plant (family Apocynaceae) indigenous to India, has medicinally important applications. A search for biochemical constituents of the latex yielded at least three thiol proteases with distinctly different properties. One them, highly active protease (ervatamin A), was purified homogeneity by ion exchange and gel filtration chromatography. The enzyme exhibited high proteolytic activity toward natural substrates amidolytic synthetic substrates. pH temperature optima were 8–8.5 50–55°C, respectively. Proteolytic strongly inhibited thiol-specific inhibitors. estimated molecular mass 27.6 kDa. extinction coefficient (e1% 280) as 21.9, protein molecule consists 8 tryptophan, 11 tyrosine 7 cysteine residues. Isoelectric point 8.37. Polyclonal antibodies raised against pure gave single precipitin line in Ouchterlony's double immunodiffusion typical color ELISA. N-terminal sequence showed conserved amino acid residues other proteases. Ervatamin shows relation isolated from same source.