Effect of imidazole on acetylcholine contracture

1969 ◽  
Vol 3 (1) ◽  
pp. 19-22
Author(s):  
A. A. Boldyrev ◽  
S. V. Bobyleva
Keyword(s):  
Acetylcholine Contracture

scholarly journals The isolation, properties and amino acid sequence of erabutoxin c, a minor neurotoxic component of the venom of a sea snake Laticauda semifasciata

1972 ◽  
Vol 130 (2) ◽  
pp. 547-555 ◽  
Author(s):  
N. Tamiya ◽  
H. Abe
Keyword(s):  
Amino Acid ◽  
Aspartic Acid ◽  
Gel Filtration ◽  
Disc Electrophoresis ◽  
Amino Acid Residues ◽  
Sea Snake ◽  
Acetylcholine Contracture ◽  
Laticauda Semifasciata ◽  
A Minor ◽  
Erabutoxin B

Erabutoxin c, a minor neurotoxic component of the venom of a sea snake Laticauda semifasciata, was isolated in pure form by repeated column chromatography on CM-cellulose columns. The toxin was crystallizable and monodisperse in rechromatography, disc electrophoresis and isoelectric focusing (isoelectric point, pH9.23–9.25). The molecular weight of the toxin, as estimated by gel filtration, was 7000. The toxin showed the same lethal activity to mice (0.13μg/g body wt., intramuscular injection) and the same effect on isolated frog muscle as erabutoxins a and b, the main toxic components of the venom. The toxin inhibited the acetylcholine contracture but not the potassium chloride contracture of muscle. Erabutoxin c consisted of 62 amino acid residues, containing one fewer lysine and one more histidine than erabutoxin a and one fewer lysine and one more aspartic acid (or asparagine) than erabutoxin b. Erabutoxin c was reduced, S-carboxymethylated and hydrolysed with trypsin. The only fragment different from the corresponding fragments from erabutoxin b was hydrolysed further with pepsin. One of the peptic fragments, which was assumed to have the aspartic acid (or asparagine) residue in question at the C-terminal end, was treated with carboxypeptidase A. The C-terminal residue was found to be an asparagine. It was therefore concluded that erabutoxin c was [51-asparagine]-erabutoxin b.

Sign in / Sign up

Export Citation Format

Share Document