title: Isolation and characterization of lethal proteins in nematocyst venom of the jellyfish Cyanea nozakii Kishinouye.
abstract: Cyanea nozakii Kishinouye, a jellyfish widely distributed in coastal areas of China, has garnered attention because of its stinging capacity and the resulting public health hazard. We used a recently developed technique to extract jellyfish venom from nematocysts; the present study investigates the lethality of C. nozakii venom. The nematocyst contents were extremely toxic to the grass carp, Ctenopharyngodon idellus, producing typical neurotoxin toxicity. The ID(50) was about 0.6microg protein/g fish. Toxin samples were stable when kept at -80( degrees )C, but after 48h, an 80% decline in lethality occurred at -20( degrees )C. Poor stability of the venom was observed within the range of 65-80( degrees )C and at pH 3.5. The venom was hydrolyzed by a proteolytic enzyme, trypsin. Fractionation of the venom yielded two protein bands with molecular weights of 60kDa and 50kDa. Our results provide the first evidence that C. nozakii produces lethal toxins. These characteristics highlight the need for the isolation and molecular characterization of new active toxins in C. nozakii.
authors.affiliation: Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Feng
authors.forename: Huahua
authors.initials: H
authors.lastname: Yu
authors.forename: Cuiping
authors.initials: C
authors.lastname: Li
authors.forename: Ronge
authors.initials: R
authors.lastname: Xing
authors.forename: Song
authors.initials: S
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.forename: Shengbao
authors.initials: S
authors.lastname: Cai
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Li
mesh_terms: D000818:Animals; D001681:Biological Assay; D002347:Carps; D002681:China; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003064:Cnidarian Venoms / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D007928:Lethal Dose 50; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D010140:Pacific Ocean; D011506:Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity*; D037401:Scyphozoa / Q000033:anatomy & histology / Q000737:chemistry* / Q000648:ultrastructure; D013696:Temperature; D013997:Time Factors
chemical_list: D003064:Cnidarian Venoms; D011506:Proteins