Novel peptide toxins from the sea anemone Stichodactyla haddoni.
Four peptide toxins, SHTX I-III with crab-paralyzing activity and SHTX IV with crab lethality, were isolated from the sea anemone Stichodactyla haddoni and their primary structures elucidated by protein sequencing and cDNA cloning. SHTX I (new toxin, 28 residues), II (analogue of SHTX I, 28 residues) and III (Kunitz-type protease inhibitor, 62 residues) are potassium channel toxins and SHTX IV (48 residues) is a member of the type 2 sea anemone sodium channel toxins. The precursor protein of SHTX IV is composed of a signal peptide, propart and mature peptide, while the propart is missing in that of SHTX III. In addition to these four toxins, an epidermal growth factor-like peptide was detected in S. haddoni by RT-PCR.
Honma
Tomohiro
T
Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Konan-4, Tokyo 108-8477, Japan.
Kawahata
Shino
S
Ishida
Masami
M
Nagai
Hiroshi
H
Nagashima
Yuji
Y
Shiomi
Kazuo
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D008387:Marine Toxins / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity*; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000633:toxicity*; D015221:Potassium Channels / Q000378:metabolism; D012615:Sea Anemones / Q000737:chemistry*; D016415:Sequence Alignment
D018076:DNA, Complementary; D008387:Marine Toxins; D010455:Peptides; D015221:Potassium Channels; C530454:SHTX-I toxin, Stichodactyla haddoni; C530455:SHTX-II toxin, Stichodactyla haddoni; C530456:SHTX-III toxin, Stichodactyla haddoni