Novel proteinaceous toxins from the nematocyst venom of the Okinawan sea anemone Phyllodiscus semoni Kwietniewski.
The Okinawan sea anemone Phyllodiscus semoni is known to cause cases of severe stinging. We isolated P. semoni toxins 60A and 60B (PsTX-60A and PsTX-60B; ca. 60 kDa) as the major toxins from the isolated nematocysts of this species for the first time. PsTX-60A and PsTX-60B showed lethal toxicity to the shrimp Palaemon paucidence when administered via intraperitoneal injection (LD(50) values: 800-900 and 800 microg/kg, respectively) and hemolytic activity toward a 0.8% suspension of sheep red blood cells (ED(50) values: 600 and 300 ng/ml, respectively). Furthermore, we sequenced the cDNA encoding PsTX-60A. The deduced amino acid sequence of PsTX-60A did not show any similarity to previously reported proteins. The N-terminal amino acid sequence of PsTX-60B showed homology with that of PsTX-60A. These toxins represent a novel class of cytolytic proteinaceous toxins.
Nagai
Hiroshi
H
Suntory Institute for Bioorganic Research, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan. nagai@tokyo-u-fish.ac.jp
Oshiro
Naomasa
N
Takuwa-Kuroda
Kyoko
K
Iwanaga
Setsuko
S
Nozaki
Masatoshi
M
Nakajima
Terumi
T
D000465:Algorithms; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D033364:Decapoda; D004912:Erythrocytes / Q000187:drug effects; D008387:Marine Toxins / Q000737:chemistry* / Q000302:isolation & purification* / Q000633:toxicity; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012615:Sea Anemones; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012756:Sheep
D018076:DNA, Complementary; D008387:Marine Toxins; C463479:TX-60A protein, Phyllodiscus semoni