CrTX-A and -B which have molecular masses of 43 and 46kDa (caliculated from SDS-PAGE result), respectively, are potent hemolytic proteinous toxins isolated from the tentacle of the box jellyfish (sea wasp) Carybdea rastoni. From the immunoblotting experiment results, it was shown that CrTX-A and CrTX-B have quite closely related molecular structure with each other. CrTX-A was mainly localized in the namatocyst and CrTX-B was detected from the tentacle and not from the nematocyst. It is proposed that there is the passway which CrTX-B was produced at first in the tentacle, then processed to CrTX-A and migrated into nematocyst. CrTX-A caused inflammation on mice skin when subcutaneously injected. Furthermore, CrTX-A showed fatal toxicity to mice with 20mg/kg (i.v.) potency. The full-length cDNA (1600 bp) which encodes CrTXs was sequenced. The deduced amino acid sequence, composed of 450 amino acids, of CrTXs shows no significant homology with any known protein. This is the first complete sequence of a jellyfish proteinous toxin to be reported.
