Structural factors affect the interactions of anticardiotoxin antibodies and cobra venom cardiotoxins.
Two antibody preparations against cardiotoxins were raised by immunizing rabbits with cardiotoxin 1 and cardiotoxin 3, respectively. The two antibody preparations showed precipitin reactions with cardiotoxins 1, 2, 3 and 5, respectively. However, the results of competitive enzyme-linked immunoassay revealed that the respective cardiotoxin molecules exhibited different reactivity toward anticardiotoxin antibodies. Moreover, the order of reactivity with antibodies was not in line with the degree of their sequence identity. This suggest that the anticardiotoxin antibodies may recognize conformational epitopes rather than sequential ones in the toxin molecules. Alternatively, the four cardiotoxins reacted well with the antibodies in the absence of competitor, suggesting that sequence variations with cardiotoxin molecules may not exclusively influence the potential use of the anticardiotoxin antibodies for the neutralization of the activity of cardiotoxin variants.
Chang
L S
LS
Department of Biochemistry, Kaohsiung Medical College, Taiwan, ROC.
Lo
Y R
YR
Lin
S R
SR
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000378:metabolism*; D001667:Binding, Competitive; D004179:Cobra Cardiotoxin Proteins / Q000737:chemistry / Q000276:immunology; D004546:Elapid Venoms / Q000737:chemistry* / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011817:Rabbits; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
D000906:Antibodies; D004179:Cobra Cardiotoxin Proteins; D004546:Elapid Venoms; C082202:cardiotoxin III, Naja naja atra; C082541:cardiotoxin V