Snake Venom Toxins

Two toxins, designated Hemachatus haemachatus toxins II and IV, have been isolated from the venom of the South African Ringhals (H. haemachatus) by gradient chromatography on Amberlite CG-50, and have been further purified by gel filtration on Sephadex G-50. The toxins are essentially homogeneous by free boundary electrophoresis, ultracentrifugation, and amino acid analyses. Toxins II and IV have electrophoretic mobilities of 7.19 x 10-5 and 4.94 x 10-5 at pH 5.0 and 2.98 x 10-5 and 2.08 x 10-5 cm2 sec-1 volt-1 at pH 8.4 and formula weights of 6838 and 6831, respectively. Both toxins contain 61 amino acid residues and are completely devoid of the amino acids alanine, methionine, and phenylalanine. The complete amino acid sequences of the two toxins have been determined and show 12 differences.