Ribonuclease from Cobra Snake Venom: Purification by Affinity Chromatography and Further Characterization

Summary A ribonuclease from cobra snake venom was isolated and purie ed to homogeneity using antibody-afe nity chromatography, increasing the yield fourfold. The purieed enzyme showed cytidylic acid specie city, as reported earlier. Further, the effects of temperature, pH, metal ions, inhibitors, and urea on the enzyme activity were studied. Snake venom RNase exhibited salt-dependent reversibleassociation‐dissociationbehaviour.Immunologicalstudies indicate that this enzyme shares one of the antigenic sites of RNase A. The partial N-terminal sequence of the enzyme showed considerable homology with phospholipases from snake venom; however, the enzyme itself did not show any phospholipase activity. IUBMBLife, 49: 309‐316, 2000