A polypeptide toxin in the sea anemone Actinia equina homologous with other sea anemone sodium channel toxins: isolation and amino acid sequence.
The sea anemone (Actinia equina) was newly established to contain a polypeptide toxin (named Ae I) having lethal activity to crabs, besides the well-known cytolytic toxins (equinatoxins) of proteinic nature. Ae I, with a minimum lethal dose against crabs of 25 micrograms/kg, was easily isolated by gel filtration on Sephadex G-50 and reverse-phase HPLC on Nucleosil 300-7C18. Its amino acid composition is characterized by the abundance of Gly, the absence of Ala and the presence of Met. The complete amino acid sequence of Ae I was determined. Ae I has high sequence homology with type 1 sea anemone neurotoxins. Interestingly, the polypeptide chain of Ae I comprises 54 amino acid residues, being 5-8 residues longer than the known type 1 toxins having 46-49 residues.
Lin
X Y
XY
Department of Food Science and Technology, Tokyo University of Fisheries, Japan.
Ishida
M
M
Nagashima
Y
Y
Shiomi
K
K
D000595:Amino Acid Sequence; D000818:Animals; D002021:Buffers; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D003064:Cnidarian Venoms / Q000302:isolation & purification / Q000378:metabolism*; D003488:Cyanogen Bromide / Q000737:chemistry; D008623:Mercaptoethanol / Q000737:chemistry; D008969:Molecular Sequence Data; D009498:Neurotoxins / Q000302:isolation & purification / Q000378:metabolism*; D010455:Peptides / Q000302:isolation & purification / Q000378:metabolism*; D012615:Sea Anemones / Q000378:metabolism*; D015222:Sodium Channels / Q000378:metabolism*
D002021:Buffers; D003064:Cnidarian Venoms; D009498:Neurotoxins; D010455:Peptides; D015222:Sodium Channels; D008623:Mercaptoethanol; D003488:Cyanogen Bromide