T. Abe, N. Tamiya
1979
Citations
0
Influential Citations
11
Citations
Quality indicators
Journal
Toxicon : official journal of the International Society on Toxinology
Abstract
Abstract Anti-erabutoxin b sera were prepared by injecting native erabutoxin b with Freund's complete adjuvant into rabbits. The anti-erabutoxin b antibodies were fractionated into ‘specific antibody’ and ‘common antibody’ by use of columns of erabutoxin b-Sepharose and toxin astrotia stokesii a-Sepharose. Inhibitory activities of erabutoxin b derivatives and of other snake neurotoxins on the binding of [3H]-[1-Na-acetylarginine]-erabutoxin b to the antibodies were measured by radioimmunossay. [1-Na-Acetylarginine]-, [15-N6-acetyl-lysine]-, [27-N6-acetyl-lysine]- and [47-N6-acetyl-lysine]-erabutoxin b and [26-Asn]-erabutoxin b (erabutoxin a) reacted with anti-erabutoxin b antibody to almost the same extent as erabutoxin b. [51-N6-Acetyl-lysine]-erabutoxin b, [51-Asn]-erabutoxin b (erabutoxin c), an erabutoxin b derivative without a hexapeptide portion (Arg-33-Glu-38) and seven toxins from other snakes, except cobrotoxin, cross-reacted with the antibody to varying extents, but reduced and S-carboxymethylated erabutoxin b and the hexapeptide Arg-33-Glu-38 gave no cross-reactions. From a comparison of the sequences of the toxins and their derivatives used in the experiments, it was concluded that among 62 amino acid residues of erabutoxin b, nine may contribute to the immunological specificity of the erabutoxin b molecule. Residues Arg-1, Gln-12, Gln-28, Ser-57 and Glu-58 may participate in the binding with ‘specific antibody’ and residues Pro-11, Ser-23, Lys-51 and Leu-52 may participate in the binding with ‘common antibody’. It is of interest that six of these residues are directed to one side of the flat erabutoxin b molecule, while only two (Pro-11 and Leu-52) point toward the other side.