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1.
Two cationic proteins, C1 and C3, were purified to homogeneity from the hemolytic fraction of the venom of Bunodosoma caissarum sea anemone. The purification processes employed gel filtration followed by ion exchange chromatography, being the purity and molecular mass confirmed by SDS-PAGE and mass spectrometry. Protein C1 represented the second major peak of the hemolytic fraction and was previously believed to be a cytolysin belonging to a new class of hemolysins. The C1 protein has a molecular mass of 15495 Da and was assayed for hemolysis, PLA2 activity and acute toxicity in crabs and mice, showing no activity in these assays. It has an amino terminal with no similarity to all known hemolysins and, therefore, should not be considered a toxin, being its function completely unknown. The protein C3 (19757 Da), that also lacks PLA2 activity, was recognized by antiserum against Eqt II and presented high hemolytic activity to human erythrocytes (ED50 of 0.270 μg/ml), being named Caissarolysin I (Bcs I). Its activity was inhibited by pre-incubation with sphingomyelin (SM) and also when in presence of erythrocytes pre-treated with the SMase P2, a phospholipase D from the brown spider Loxosceles intermedia, indicating that SM is the main target of Bcs I. Caissarolysin I is the first hemolysin purified from a sea anemone belonging to the genus Bunodosoma and belongs to the Actinoporin family of sea anemone hemolysins.  相似文献   

2.
Src I is the first reported acidic actinoporin from sea anemone Sagartia rosea with a pI value of 4.8 and comprises 13.9% alpha-helix, 65.1% beta-sheet, and 18.2% random coil. For structure-function studies, Src I was expressed in Escherichia coli as a cleavable fusion protein. Recombinant Src I exhibited obviously hemolytic activity, but the fusion protein Trx-Src I almost lost its hemolytic activity, suggesting the importance of the N-terminal amphiphilic alpha-helix for its functional activity. The cytotoxic effects of Src I depending on the toxin concentration and incubation time were also observed on cultured cells. Among five cell lines: NIH/3T3, U251, NSCLC, BEL-7402, and BGC-823, NSCLC was the most sensitive cells with ID(50) 2.8 microg/ml and BGC-823 was the least sensitive cells with ID(50) 7.4 microg/ml. After incubated with lipid SUVs, such as SM-SUVs and SM/PC-SUVs, the hemolytic activity of Src I was inhibited to some extent. When incubated with calcein-entrapped lipid LUVs, such as SM-LUVs, SM/PC-LUVs, and SM/PG-LUVs, Src I induced release of entrapped calcein. According to the interaction with lipid vesicles, we proposed that it was the membrane matrix made up of phospholipids, not a particular phospholipid that facilitates Src I to react properly.  相似文献   

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This work aimed at the isolation and structural/functional characterization of a phospholipase A2 (CgPLA2) from the extract of the anemone Condylactis gigantea. CgPLA2 was isolated with a high purity level through three chromatographic steps, showing pI ˜ 8.6 and molecular weights of 14,500 and 29,000 for the monomer and dimer, respectively. CgPLA2 showed a high catalytic activity upon fluorescent phospholipids inducing no direct hemolytic activity. This enzyme, which is Ca2+-dependent, showed a lower stability against temperature and pH variations when compared with snake venom enzymes. The enzymatic activity was significantly reduced or completely abolished after chemical modification of CgPLA2 with BPB. Its cDNA was then obtained, with 357 base pairs which codified for a mature protein of 119 amino acid residues. A comparative analysis of the primary structure of CgPLA2 revealed 84%, 61%, 43% and 42% similarity to the PLA2s from Adamsia carciniopados, Nematostella vectensis, Vipera russelli russelli and Bothrops jararacussu, respectively.  相似文献   

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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.  相似文献   

7.
The genes of four novel neurotoxins, named Hk2a, Hk7a, Hk8a, and Hk16a, were obtained from sea anemone Anthopleura sp. All four neurotoxins were composed of 47 amino acid residues and the variable residues among them were found in positions 14, 22, 25, and 37. To study their activities, the four toxins fused to the Escherichia coli thioredoxin were overexpressed by BL21 (DE3), cleaved off from the fusion partner, purified, and characterized with MALDI-TOF and CD assays. Contractile force studies of isolated SD atria indicated that rHk2a had the strongest and rHk7a the longest heart stimulation effect. Consequently, the Arg14, a highly conserved residue in various sea anemone neurotoxins, can be inferred to contribute to the duration but not the intensity of contraction-stimulating activity. Our work renders useful information to studies of sea anemone neurotoxins, especially to the clarification of the function of the disputative Arg14.  相似文献   

8.
A cytolytic toxin from the sea anemone Condylactis gigantea was isolated and characterized as a thermolabile basic protein (pI 8.9) having a molecular weight of 18,300. It lacks methionine but contains relatively large amounts of glycine, serine, tryptophan, and half-cystine. Its hemolytic action is inhibited by sphingomyelin. It is lytic for rabbit blood platelets, is lethal in low concentration for crayfish (LD50 = 0.06 μg), and may be identical with a neurotoxic protein isolated earlier from the same species. It broadly resembles the toxin of Stoichactis helianthus but differs from it in amino acid composition and in minor respects.  相似文献   

9.
The full-length cDNA that encodes the hemolytic toxin Avt-I, with 226 amino acids, from the venomous sea anemone Actineria villosa has been cloned using the oligo-capping method. The cDNA contains 681bp open reading frame and its predicted amino acid sequences revealed that Avt-I was basic polypeptides without cysteine residues and Arg-Gly-Asp (RGD) motif sequence. The mature Avt-I has a predicted molecular weight of 19.6 kDa and its theoretical isoelectric point is 9.3. The Avt-I revealed 99, 61, 57, and 57% amino acid similarity with hemolytic toxins Pstx20, EqtII, StII, and HmT from Phyllodiscus semoni, Actinia Equina, Stichodactyla helianthus, and Heteractis magnifica, respectively. The characteristic amphiphilic alpha-helix structure was found at the N-terminal region of the mature Avt-I. Recombinant Avt-I (rAvt-I) was expressed in Escherichia coli BL21 (DE3) strain as a biologically active form and purified rAvt-I caused 50% hemolytic activity against 1% sheep erythrocytes at a concentration of 6.3 ng/ml (0.32 nM). M9Y medium led to more than 2-fold increase in rAvt-I yield than cultivation in Luria-Bertani medium.  相似文献   

10.
Xin S  Jian-Xiu C  Louis D 《ZooKeys》2011,(78):27-41
In this paper, we describe a new species of the genus Allonychiurus Yoshii, 1995, characterized by the presence of an apical swelling on the fourth antennal segment as well as a combination of chaetotaxic and pseudocellar characters. The genus Allonychiurus is redefined. Four of its species are considered as incertae sedis: Allonychiurus michelbacheri (Bagnall, 1948), Allonychiurus spinosus (Bagnall, 1949), Allonychiurus caprariae (Dallai, 1969) and Allonychiurus sensitivus (Handschin, 1928). The three species Allonychiurus borensis (Beruete, Arbea & Jordana, 1994), Allonychiurus sensilatus (Thibaud & Massoud, 1979) and Allonychiurus vandeli (Cassagnau, 1960) are removed from Allonychiurus and placed in Micronychiurus Bagnall, 1949, Thalassaphorura Bagnall, 1949 and Spinonychiurus Weiner, 1996 respectively. The synonymy of Thibaudichiurus Weiner, 1996 with Allonychiurus is rejected and Allonychiurus foliatus (Rusek, 1967) and Allonychiurus mariangeae (Thibaud & Lee, 1994) are re-allocated to Thibaudichiurus. List and identification key to the world species of the genus are given.  相似文献   

11.
The species of the subfamily Opiinae (Hymenoptera: Braconidae) from Hunan (Oriental China) are revised and illustrated. Thirty-six new species are described: Apodesmia bruniclypealis Li & van Achterberg, sp. n., Apodesmia melliclypealis Li & van Achterberg, sp. n., Areotetes albiferus Li & van Achterberg, sp. n., Areotetes carinuliferus Li & van Achterberg, sp. n., Areotetes striatiferus Li & van Achterberg, sp. n., Coleopioides diversinotum Li & van Achterberg, sp. n., Coleopioides postpectalis Li & van Achterberg, sp. n., Fopius dorsopiferus Li, van Achterberg & Tan, sp. n., Indiopius chenae Li & van Achterberg, sp. n., Opiognathus aulaciferus Li & van Achterberg, sp. n., Opiognathus brevibasalis Li & van Achterberg, sp. n., Opius crenuliferus Li & van Achterberg, sp. n., Opius malarator Li, van Achterberg & Tan, sp. n., Opius monilipalpis Li & van Achterberg, sp. n., Opius pachymerus Li & van Achterberg, sp. n., Opius songi Li & van Achterberg, sp. n., Opius youi Li & van Achterberg, sp. n., Opius zengi Li & van Achterberg, sp. n., Phaedrotoma acuticlypeata Li & van Achterberg, sp. n., Phaedrotoma angiclypeata Li & van Achterberg, sp. n., Phaedrotoma antenervalis Li & van Achterberg, sp. n., Phaedrotoma depressiclypealis Li & van Achterberg, sp. n., Phaedrotoma flavisoma Li & van Achterberg, sp. n., Phaedrotoma nigrisoma Li & van Achterberg, sp. n., Phaedrotoma protuberator Li & van Achterberg, sp. n., Phaedrotoma rugulifera Li & van Achterberg, sp. n., Li & van Achterberg,Phaedrotoma striatinota Li & van Achterberg, sp. n., Phaedrotoma vermiculifera Li & van Achterberg, sp. n., Rhogadopsis latipennis Li & van Achterberg, sp. n., Rhogadopsis longicaudifera Li & van Achterberg, sp. n., Rhogadopsis maculosa Li, van Achterberg & Tan, sp. n., Rhogadopsis obliqua Li & van Achterberg, sp. n., Rhogadopsis sculpturator Li & van Achterberg, sp. n., Utetes longicarinatus Li & van Achterberg, sp. n. and Xynobius notauliferus Li & van Achterberg, sp. n. Areotetes van Achterberg & Li, gen. n. (type species: Areotetes carinuliferus sp. n.) and Coleopioides van Achterberg & Li, gen. n. (type species: Coleopioides postpectalis sp. n. are described. All species are illustrated and keyed. In total 30 species of Opiinae are sequenced and the cladograms are presented. Neopius Gahan, 1917, Opiognathus Fischer, 1972, Opiostomus Fischer, 1972, and Rhogadopsis Brèthes, 1913, are treated as a valid genera based on molecular and morphological differences. Opius vittata Chen & Weng, 2005 (not Opius vittatus Ruschka, 1915), Opius ambiguus Weng & Chen, 2005 (not Wesmael, 1835) and Opius mitis Chen & Weng, 2005 (not Fischer, 1963) are primary homonymsandarerenamed into Phaedrotoma depressa Li & van Achterberg, nom. n., Opius cheni Li & van Achterberg, nom. n. andOpius wengi Li & van Achterberg, nom. n., respectively. Phaedrotoma terga (Chen & Weng, 2005) comb. n.,Diachasmimorpha longicaudata (Ashmead, 1905) and Biosteres pavitita Chen & Weng, 2005, are reported new for Hunan, Opiostomus aureliae (Fischer, 1957) comb. n. is new for China and Hunan; Xynobius maculipennis(Enderlein, 1912) comb. n. is new for Hunan and continental China and Rhogadopsis longuria (Chen & Weng, 2005) comb. n. is new for Hunan. The following new combinations are given: Apodesmia puncta (Weng & Chen, 2005) comb. n., Apodesmia tracta (Weng & Chen, 2005) comb. n., Areotetes laevigatus (Weng & Chen, 2005) comb. n., Phaedrotoma dimidia (Chen & Weng, 2005) comb. n., Phaedrotoma improcera (Weng & Chen, 2005) comb. n., Phaedrotoma amputata (Weng & Chen, 2005) comb. n., Phaedrotoma larga (Weng & Chen, 2005) comb. n., Phaedrotoma osculas (Weng & Chen, 2005) comb. n., Phaedrotoma postuma (Chen & Weng, 2005) comb. n., Phaedrotoma rugulosa (Chen & Weng, 2005) comb. n., Phaedrotoma tabularis (Weng & Chen, 2005) comb. n., Rhogadopsis apii (Chen & Weng, 2005) comb. n., Rhogadopsis dimidia (Chen & Weng, 2005) comb. n., Rhogadopsis diutia (Chen & Weng, 2005) comb. n., Rhogadopsis longuria (Chen & Weng, 2005) comb. n., Rhogadopsis pratellae(Weng & Chen, 2005) comb. n., Rhogadopsis pratensis (Weng & Chen, 2005) comb. n., Rhogadopsis sculpta (Chen & Weng, 2005) comb. n., Rhogadopsis sulcifer (Fischer, 1975) comb. n., Rhogadopsis tabidula(Weng & Chen, 2005) comb. n., Xynobius complexus (Weng & Chen, 2005) comb. n., Xynobius indagatrix (Weng & Chen, 2005) comb. n., Xynobius multiarculatus (Chen & Weng, 2005) comb. n.The following (sub)genera are synonymised: Snoflakopius Fischer, 1972, Jucundopius Fischer, 1984, Opiotenes Fischer, 1998, and Oetztalotenes Fischer, 1998, with Opiostomus Fischer, 1971; Xynobiotenes Fischer, 1998, with Xynobius Foerster, 1862; Allotypus Foerster, 1862, Lemnaphilopius Fischer, 1972, Agnopius Fischer, 1982, and Cryptognathopius Fischer, 1984, with Apodesmia Foerster, 1862; Nosopoea Foerster, 1862, Tolbia Cameron, 1907, Brachycentrus Szépligeti, 1907, Baeocentrum Schulz, 1911, Hexaulax Cameron, 1910, Coeloreuteus Roman, 1910, Neodiospilus Szépligeti, 1911, Euopius Fischer, 1967, Gerius Fischer, 1972, Grimnirus Fischer, 1972, Hoenirus Fischer, 1972, Mimirus Fischer, 1972, Gastrosema Fischer, 1972, Merotrachys Fischer, 1972, Phlebosema Fischer, 1972, Neoephedrus Samanta, Tamili, Saha & Raychaudhuri, 1983, Adontopius Fischer, 1984, Kainopaeopius Fischer, 1986, Millenniopius Fischer, 1996, and Neotropopius Fischer, 1999, with Phaedrotoma Foerster, 1862.  相似文献   

12.
The identification and characterization of antigens that elicit human T cell responses is an important step toward understanding of Leishmania major infection and ultimately in the development of a vaccine. Micropreparative SDS-PAGE followed by electrotransfer to a PVDF membrane and elution of proteins from the PVDF, was used to separate 2 novel proteins from L. major promastigotes, which can induce antibodies of the IgG2a isotype in mice and also are recognized by antisera of recovered human cutaneous leishmaniasis subjects. Fractionation of the crude extract of L. major revealed that all detectable proteins of interest were present within the soluble Leishmania antigens (SLA). Quantitation of these proteins showed that their expression in promastigotes is relatively very low. Considering the molecular weight, immunoreactivity, chromatographic and electrophoretic behavior in reducing and non-reducing conditions, these proteins are probably 2 isoforms of a single protein. A digest of these proteins was resolved on Tricine-SDS-PAGE and immunoreactive fragments were identified by human sera. Two immunoreactive fragments (36.4 and 34.8 kDa) were only generated by endoproteinase Glu-C treatment. These immunoreactive fragments or their parent molecules may be ideal candidates for incorporation in a cocktail vaccine against cutaneous leishmaniasis.  相似文献   

13.
Molecular phylogenetic evidence indicates that the octocoral family Alcyoniidae is highly polyphyletic, with genera distributed across Octocorallia in more than 10 separate clades. Most alcyoniid taxa belong to the large and poorly resolved Holaxonia–Alcyoniina clade of octocorals, but members of at least four genera of Alcyoniidae fall outside of that group. As a first step towards revision of the family, we describe a new genus, Parasphaerasclera gen. n., and family, Parasphaerascleridae fam. n., of Alcyonacea to accommodate species of Eleutherobia Pütter, 1900 and Alcyonium Linnaeus, 1758 that have digitiform to digitate or lobate growth forms, completely lack sclerites in the polyps, and have radiates or spheroidal sclerites in the colony surface and interior. Parasphaerascleridae fam. n. constitutes a well-supported clade that is phylogenetically distinct from all other octocoral taxa. We also describe a new genus of Alcyoniidae, Sphaerasclera gen. n., for a species of Eleutherobia with a unique capitate growth form. Sphaerasclera gen. n. is a member of the Anthomastus–Corallium clade of octocorals, but is morphologically and genetically distinct from Anthomastus Verrill, 1878 and Paraminabea Williams & Alderslade, 1999, two similar but dimorphic genera of Alcyoniidae that are its sister taxa. In addition, we have re-assigned two species of Eleutherobia that have clavate to capitate growth forms, polyp sclerites arranged to form a collaret and points, and spindles in the colony interior to Alcyonium, a move that is supported by both morphological and molecular phylogenetic evidence.  相似文献   

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The genus Paramunida belongs to the most diverse family of galatheoids and it is commonly reported from the continental slope across the Indian and Pacific Oceans. Examination of material collected by the NOAA RV Townsend Cromwell Cruise near Christmas (Kiritimati) Island, Kiribati, revealed the existence of a new species of Paramunida (P. haigae), which represents the fourth record of the genus for the Central Pacific. Furthermore, recent efforts to unravel phylogenetic relationships and diversification patterns in Paramunida revealed P. granulata (Henderson, 1885) to be the most basally diverging taxon within the genus. This species is clearly distinguished from other species of Paramunida by the spinulation of the carapace and the length of the distomesial spine of the second antennal peduncle article, which in combination with a high level of genetic divergence suggest that this species represents a separate monotypic lineage. A new genus, Hendersonida gen. n., is proposed to accommodate this species based on morphological and molecular evidence. An updated dichotomous identification key for all species of Paramunida is presented.  相似文献   

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The Australian Thrasorinae are revised and Mikeius is transferred to Mikeiinae Paretas-Martínez & Pujade-Villar, subfam. n., and Mikeius clavatus Pujade-Villar & Restrepo-Ortiz, sp. n., is described. Two new genera of Thrasorinae are erected: Cicatrix Paretas-Martínez, gen. n., including Cicatrix pilosiscutum(Girault), comb. n. from Amblynotus, Cicatrix schauffi (Buffington), comb. n. from Mikeius, and Cicatrix neumannoides Paretas-Martínez & Restrepo-Ortiz, sp. n.; and Palmiriella Pujade-Villar & Paretas-Martínez, gen. n., including Palmiriella neumanni (Buffington), comb. n. from Mikeius, Thrasorus rieki Paretas-Martínez & Pujade-Villar, sp. n., is also described. A phylogenetic analysis of 176 morphological and biological characters, including all these new taxa and all genera previously included in Thrasorinae, was conducted. All subfamilies were recovered as monophyletic, with the following relationships: Parnipinae (Euceroptrinae (Mikeiinae (Plectocynipinae (Thrasorinae)))). A worldwide key to the subfamilies of Figitidae is provided that includes the new subfamily, as well as a key to genera Thrasorinae.  相似文献   

18.
An epidermal growth factor (EGF)-like toxin (gigantoxin I) and two sodium channel toxins (gigantoxins II and III), previously isolated from the sea anemone Stichodactyla gigantea, were cloned for their cDNAs. The precursor protein of gigantoxin I is composed of a signal peptide, propart and mature peptide, similar to those of gigantoxins II and III, and is much simpler in structure than those of mammalian EGFs. In addition, gigantoxin I as well as gigantoxins II and III was demonstrated to be contained in nematocysts, suggesting that gigantoxin I functions as a toxin in S. gigantea.  相似文献   

19.
Tarka and Tarkadectes are Middle Eocene mammals known only from the Rocky Mountains region of North America. Previous work has suggested that they are members of the Plagiomenidae, an extinct family often included in the order Dermoptera. Here we describe a new primate, Tarkops mckennai gen. et sp. nov., from the early Middle Eocene Irdinmanha Formation of Inner Mongolia, China. The new taxon is particularly similar to Tarka and Tarkadectes, but it also displays many features observed in omomyids. A phylogenetic analysis based on a data matrix including 59 taxa and 444 dental characters suggests that Tarkops, Tarka and Tarkadectes form a monophyletic group—the Tarkadectinae—that is nested within the omomyid clade. Within Omomyidae, tarkadectines appear to be closely related to Macrotarsius. Dermoptera, including extant and extinct flying lemurs and plagiomenids, is recognized as a clade nesting within the polyphyletic group of plesiadapiforms, therefore supporting the previous suggestion that the relationship between dermopterans and primates is as close as that between plesiadapiforms and primates. The distribution of tarkadectine primates on both sides of the Pacific Ocean basin suggests that palaeoenvironmental conditions appropriate to sustain primates occurred across a vast expanse of Asia and North America during the Middle Eocene.  相似文献   

20.
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