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Dayong Zhou - One of the best experts on this subject based on the ideXlab platform.
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effects of endogenous cysteine proteinases on structures of collagen fibres from dermis of sea cucumber Stichopus japonicus
Food Chemistry, 2017Co-Authors: Yuxin Liu, Kunihiko Konno, Dayong Zhou, Ziqiang Liu, Yanfei Liu, Liang Song, Xiuping Dong, Beiwei Zhu, Fereidoon ShahidiAbstract:Autolysis of sea cucumber, caused by endogenous enzymes, leads to postharvest quality deterioration of sea cucumber. However, the effects of endogenous proteinases on structures of collagen fibres, the major biologically relevant substrates in the body wall of sea cucumber, are less clear. Collagen fibres were prepared from the dermis of sea cucumber (Stichopus japonicus), and the structural consequences of degradation of the collagen fibres caused by endogenous cysteine proteinases (ECP) from Stichopus japonicus were examined. Scanning electron microscopic images showed that ECP caused partial disaggregation of collagen fibres into collagen fibrils by disrupting interfibrillar proteoglycan bridges. Differential scanning calorimetry and Fourier transform infrared analysis revealed increased structural disorder of fibrillar collagen caused by ECP. SDS-PAGE and chemical analysis indicated that ECP can liberate glycosaminoglycan, hydroxyproline and collagen fragments from collagen fibres. Thus ECP can cause disintegration of collagen fibres by degrading interfibrillar proteoglycan bridges.
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changes in collagenous tissue microstructures and distributions of cathepsin l in body wall of autolytic sea cucumber Stichopus japonicus
Food Chemistry, 2016Co-Authors: Yuxin Liu, Dayong Zhou, Yanfei Liu, Xiuping Dong, Mingqian Tan, Beiwei ZhuAbstract:The autolysis of sea cucumber (Stichopus japonicus) was induced by ultraviolet (UV) irradiation, and the changes of microstructures of collagenous tissues and distributions of cathepsin L were investigated using histological and histochemical techniques. Intact collagen fibers in fresh S. japonicus dermis were disaggregated into collagen fibrils after UV stimuli. Cathepsin L was identified inside the surface of vacuoles in the fresh S. japonicus dermis cells. After the UV stimuli, the membranes of vacuoles and cells were fused together, and cathepsin L was released from cells and diffused into tissues. The density of cathepsin L was positively correlated with the speed and degree of autolysis in different layers of body wall. Our results revealed that lysosomal cathepsin L was released from cells in response to UV stimuli, which contacts and degrades the extracellular substrates such as collagen fibers, and thus participates in the autolysis of S. japonicus.
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purification and partial characterisation of a cathepsin l like proteinase from sea cucumber Stichopus japonicus and its tissue distribution in body wall
Food Chemistry, 2014Co-Authors: Dayong Zhou, Yuxin Liu, Liang Song, Xiuping Dong, Beiwei Zhu, Xian Na Chang, Sha Sha Bao, Yuan Zong, Mao Mao Zhang, Yoshiyuki MurataAbstract:Abstract A cathepsin L-like proteinase (CLP) with molecular weight of 30.9 kDa from the gut of sea cucumber ( Stichopus japonicas , S. japonicus ) was isolated and purified to homogeneity by several chromatographic procedures. The enzyme exhibited optimum activity at pH 5.0–5.5 and 50 °C, and showed thermostability up to 40 °C. The enzyme activity was completely inhibited by Zn 2+ , strongly inhibited by Fe 2+ and Cu 2+ , drastically reduced by cysteine proteinase inhibitors, but slightly enhanced by thiol-activating agents. The enzyme efficiently hydrolysed the specific substrate of cathepsin L, but hardly hydrolysed the specific substrates for cathepsin B, cathepsin H and cathepsin K. Immunohistochemical studies indicated that the CLP was more abundant in the epidermis rather than in the dermis of S. japonicus body wall. The distribution of CLP showed positive correlation with autolysis rate. Therefore, the relationship between CLP and autolysis deserved further study.
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physicochemical properties and radical scavenging capacities of pepsin solubilized collagen from sea cucumber Stichopus japonicus
Food Hydrocolloids, 2012Co-Authors: Xiuping Dong, Hai Tao Wu, Dongmei Li, Dayong Zhou, Jingfeng Yang, Xingkun Zhao, Wenxiu Ye, Chenxu YuAbstract:Abstract Pepsin-solubilized collagen (PSC) was successfully prepared from the body wall of sea cucumber Stichopus japonicus . Ultraviolet–visible and Fourier transform infrared spectroscopic analyses showed that the PSC was a high-purity collagen that maintained the intact triple-stranded helices. Physical and chemical characterization of the PSC showed a isoelectric point of 4.14, a superior moisture-absorption and retention capacities comparing to glycerol, a minimum solubility at pH 5.0 in 0.5 M acetic acid, and a sharp decrease in solubility in the presence of low concentration of NaCl. The viscosity of PSC was shown to decrease continuously as the temperature was increased. The radical scavenging activity of the PSC was characterized with two model systems: for hydroxyl radicals, the PSC was more active than vitamin C but less active than sulfourea; for 1,1-diphenyl-2-picrylhydrazyl radicals, the PSC was more active than vitamin E.
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purification and characterization of cathepsin b from the gut of the sea cucumber Stichopus japonicas
Food Science and Biotechnology, 2011Co-Authors: Li Ming Sun, Dayong Zhou, Xiuping Dong, Beiwei Zhu, Jingfeng Yang, Yoshiyuki MurataAbstract:Cathepsin B from the gut of sea cucumber (Stichopus japonicas) was purified 81-fold with a 3% recovery by ammonium sulfate fractionation and a series chromatography on DEAE Sepharose CL-6B, Sephadex G-75, and TSK-Gel 3000 SWxl. The purified protein appeared as a single band on Native-PAGE but showed 2 bands of 23 and 26 kDa on SDS-PAGE. The optimum activity was found at pH 5.5 and 45°C. The enzyme was stable at pH 4.5–6.0 and the thermal stability was up to 50oC. The enzyme was strongly inhibited by E-64, iodoacetic acid, and antipain, demonstrating it is a cysteine protease containing sulfhydryl groups. Cu2+, Ni2+, and Zn2+ could strongly inhibit the enzyme activity. The amino acid sequences of the purified enzyme were acquired by mass spectrometer, which did not show any homology with previously described cathepsins, suggesting it may be a novel member.
Sigang Fan - One of the best experts on this subject based on the ideXlab platform.
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complete mitochondrial genome of the sea cucumber Stichopus sp and its application in the identification of this species
Aquaculture Research, 2012Co-Authors: Sigang Fan, Lvping Zhang, Hongyan Sun, Jing Wen, Peng LuoAbstract:The complete sequence of mitochondrial DNA (mtDNA) from Stichopus sp. (Echinodermata: Holothuroidea: Stichopodidae: Stichopus) was acquired using conventional PCR and long PCR followed by cloning and sequencing. The mtDNA is a circular molecule of 16 similar to 257 similar to bp in length, containing the set of 37 genes, including 13 protein-coding genes (PCGs), 22 tRNA genes and two ribosomal RNA genes. The plus strand consists of 30.9% A, 23.7% C, 16.0% G and 29.3% T bases (AT skew similar to=similar to 0.027; GC skew similar to=similar to-0.194). All 13 PCGs encode a total of 3782 amino acids and all 22 tRNA genes were predicted to be capable of folding into a clover-leaf secondary structure. Intergenetic regions in the mitochondrial genome of Stichopus sp. contain 903 similar to bp in total, with the largest continuous region (674 similar to bp, AT%similar to=similar to 58.6) between tRNA-Thr and tRNA-Pro. Analysis of phylogenetic relationship of family Stichopodidae and genetic distances (species among the family Stichopodidae and species within Stichopus monotuberculatus group) based on the partial cox1 sequence demonstrates that Stichopus sp. from the South China Sea is a member of S. monotuberculatus complex.
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Characterization of mitochondrial genome of sea cucumber Stichopus horrens: A novel gene arrangement in Holothuroidea
Science China. Life sciences, 2011Co-Authors: Sigang Fan, Jing Wen, Lvping ZhangAbstract:The complete mitochondrial DNA sequence contains useful information for phylogenetic analyses of metazoa. In this study, the complete mitochondrial DNA sequence of sea cucumber Stichopus horrens (Holothuroidea: Stichopodidae: Stichopus) is presented. The complete sequence was determined using normal and long PCRs. The mitochondrial genome of Stichopus horrens is a circular molecule 16257 bps long, composed of 13 protein-coding genes, two ribosomal RNA genes and 22 transfer RNA genes. Most of these genes are coded on the heavy strand except for one protein-coding gene (nad6) and five tRNA genes (tRNA Ser(UCN) , tRNA Gln , tRNA Ala , tRNA Val , tRNA Asp ) which are coded on the light strand. The composition of the heavy strand is 30.8% A, 23.7% C, 16.2% G, and 29.3% T bases (AT skew=0.025; GC skew=−0.188). A non-coding region of 675 bp was identified as a putative control region because of its location and AT richness. The intergenic spacers range from 1 to 50 bp in size, totaling 227 bp. A total of 25 overlapping nucleotides, ranging from 1 to 10 bp in size, exist among 11 genes. All 13 protein-coding genes are initiated with an ATG. The TAA codon is used as the stop codon in all the protein coding genes except nad3 and nad4 that use TAG as their termination codon. The most frequently used amino acids are Leu (16.29%), Ser (10.34%) and Phe (8.37%). All of the tRNA genes have the potential to fold into typical cloverleaf secondary structures. We also compared the order of the genes in the mitochondrial DNA from the five holothurians that are now available and found a novel gene arrangement in the mitochondrial DNA of Stichopus horrens.
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larval development and juvenile growth of the sea cucumber Stichopus sp curry fish
Aquaculture, 2010Co-Authors: Jing Wen, Lvping Zhang, Sigang FanAbstract:The global populations of Curry fish have been severely depleted over the past decade. This study describes spawning, fertilization, larval rearing, and juvenile growth in a commercially important Stichopus species. Data pooled from monthly trials conducted over 2 years indicate that, under optimal conditions, juveniles can be grown to a size of ca. 20 cm in length in 7 months. The survival rates are typically between 30 and 50%. Pilot research indicates that the growth of young sea cucumbers in abandoned abalone tanks has potential. Overall, this study demonstrates that Curry fish can be reared in captivity, thus providing an alternative to fisheries. or a way to maintain sustainable harvests and eventually contribute to the restoration of the natural populations. (C) 2009 Elsevier B.V. All rights reserved.
Maria Byrne - One of the best experts on this subject based on the ideXlab platform.
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Description and phylogenetic relationships of a new genus of sea cucumbers from Australia, with two new combinations (Holothuroidea, Stichopodidae)
Marine Biodiversity, 2019Co-Authors: Sau Pinn Woo, Hiroshi Kajihara, Maria Byrne, Toshihiko FujitaAbstract:A new genus of Holothuroidea, NotoStichopus , from Australia is described and its phylogenetic relationship examined. The new genus is based on two species within the family Stichopodidae, previously attributed to Stichopus . NotoStichopus is characterized by the absence of rosette ossicles and the presence of table ossicles with at most one crossbeam in dorsal body wall. The two species revised here ( N. ludwigi and N. ellipes ) are distributed in the shallow, tropical, and temperate waters of Australia. Phylogenetic analyses indicate that this genus is closely related to the genera IsoStichopus and Stichopus but is distinct based on ossicles and phylogenetic analyses. We describe the ossicle assemblages of both species.
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gonad development and spawning of the vulnerable commercial sea cucumber Stichopus herrmanni in the southern great barrier reef
Journal of the Marine Biological Association of the United Kingdom, 2019Co-Authors: Regina Balogh, Kennedy Wolfe, Maria ByrneAbstract:Despite the important ecological roles of commercial beche-de-mer holothuroids in coral reef ecosystems their reproductive biology is poorly studied, including on the Great Barrier Reef (GBR). We investigated reproduction of Stichopus herrmanni , a commercially important species listed as Vulnerable, at One Tree Island, southern GBR. Gonad index, histology and spawning observations indicated an annual reproductive cycle with gamete release in the Austral spring and summer (November–February), as for populations of this species at a similar latitude in New Caledonia. Stichopus herrmanni releases gametes episodically, spawning multiple times during summer. Assimilation of spawning observations from OTI and elsewhere along the GBR and tropical Pacific revealed that gamete release by S. herrmanni is influenced by the lunar cycle, with spawning taking place around the new moon in summer. This species is an aggregative spawner with a behavioural change to attain elevated positions on the reef at dusk prior to spawning. After the spawning season, gametes remaining in the gonads are reabsorbed. Spent gonads completely lacked gametes. There was a quiescence in gonad development in winter with an absence of gonads in some specimens, indicating an aestivation-like period for reproduction. By late-winter (August) recovery stage gonads were distinguished by the initiation of gametogenesis, which coincided with increasing temperature and day length. Our findings contribute to the understanding of the reproductive biology of S. herrmanni , a consideration for future fisheries management in the protection of this Vulnerable species, especially with respect to the increasing global trade in beche-de-mer.
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altered sediment biota and lagoon habitat carbonate dynamics due to sea cucumber bioturbation in a high pco2 environment
Global Change Biology, 2018Co-Authors: Kennedy Wolfe, Francisco Vidalramirez, Sophie Dove, Dione Deaker, Maria ByrneAbstract:The effects of global change on biological systems and functioning are already measurable, but how ecological interactions are being altered is poorly understood. Ecosystem resilience is strengthened by ecological functionality, which depends on trophic interactions between key species and resilience generated through biogenic buffering. Climate-driven alterations to coral reef metabolism, structural complexity and biodiversity are well documented, but the feedbacks between ocean change and trophic interactions of non-coral invertebrates are understudied. Sea cucumbers, some of the largest benthic inhabitants of tropical lagoon systems, can influence diel changes in reef carbonate dynamics. Whether they have the potential to exacerbate or buffer ocean acidification over diel cycles depends on their relative production of total alkalinity (AT) through the dissolution of ingested calcium carbonate (CaCO3) sediments and release of dissolved inorganic carbon (CT) through respiration and trophic interactions. In this study, the potential for the sea cucumber, Stichopus herrmanni, a beche-de-mer (fished) species listed as vulnerable to extinction, to buffer the impacts of ocean acidification on reef carbonate chemistry was investigated in lagoon sediment mesocosms across diel cycles. Stichopus herrmanni directly reduced the abundance of meiofauna and benthic primary producers through its depositfeeding activity under present-day and near-future pCO(2). These changes in benthic community structure, as well as AT (sediment dissolution) and CT (respiration) production by S. herrmanni, played a significant role in modifying seawater carbonate dynamics night and day. This previously unappreciated role of tropical sea cucumbers, in support of ecosystem resilience in the face of global change, is an important consideration with respect to the beche-de-mer trade to ensure sea cucumber populations are sustained in a future ocean.
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molecular taxonomy phylogeny and evolution in the family stichopodidae aspidochirotida holothuroidea based on coi and 16s mitochondrial dna
Molecular Phylogenetics and Evolution, 2010Co-Authors: Maria Byrne, Frank W E Rowe, Sven UthickeAbstract:Abstract The Stichopodidae comprise a diverse assemblage of holothuroids most of which occur in the Indo-Pacific. Phylogenetic analyses of mitochondrial gene (COI, 16S rRNA) sequence for 111 individuals (7 genera, 17 species) clarified taxonomic uncertainties, species relationships, biogeography and evolution of the family. A monophyly of the genus Stichopus was supported with the exception of Stichopus ellipes . Molecular analyses confirmed genus level taxonomy based on morphology. Most specimens harvested as S. horrens fell in the S. monotuberculatus clade, a morphologically variable assemblage with others from the S. naso clade. Taxonomic clarification of species fished as S. horrens will assist conservation measures. Evolutionary rates based on comparison of sequence from trans-ithmian IsoStichopus species estimated that Stichopus and IsoStichopus diverged ca. 5.5–10.7 Ma (Miocene). More recent splits were estimated to be younger than 1 Ma.
G. B. Elyakov - One of the best experts on this subject based on the ideXlab platform.
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Mechanism of cytotoxic action of some triterpene glycosides
Toxicon, 2002Co-Authors: M.m. Anisimov, E.b. Shentsova, V.v. Shcheglov, Yu.n. Shumilov, V. A. Rasskazov, L.i. Strigina, N. S. Chetyrina, G. B. ElyakovAbstract:Abstract A study was carried out to elucidate the effects of triterpene glycosides of stichoposide A from Stichopus japonicus S., caulosides B and C from Caulophyllum robustum M., aescin from Aesculus hippocastarus L. and theasaponin from Thea sinensis L., upon the biosynthesis of nucleic acids and protein in the embryo culture of the sea urchin and upon selective permeability of cell membranes. The cytotoxic activity, in sea urchin embryos, of the triterpene glycosides and inhibition of macromolecule synthesis appeared to be due to an alteration in the selective permeability of the cytoplasmic membrane. Triterpene glycosides suppress nucleoside and amino acid transport into the cell and stimulate the efflux of u.v.-absorbing substances from the cell.
Chunhua Ren - One of the best experts on this subject based on the ideXlab platform.
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characterization of a main extracellular matrix autoenzyme from the dermis of sea cucumber Stichopus monotuberculatus collagenase
International Journal of Food Properties, 2016Co-Authors: Ming Zhong, Chunhua Ren, Xing Luo, Yiming CaiAbstract:Sea cucumber is easy to undergo autolysis, causing serious economic loss in the aquaculture, fishery, and food processing. However, research on the autolysis of sea cucumber is limited. In the present study, the autoenzyme that could hydrolyze the structural protein of body wall was identified and characterized in sea cucumber Stichopus monotuberculatus. Although the main edible part of sea cucumber was the body wall, its microstructure was shown to be almost composed of collagen fibers belonging to extracellular matrix, indicating that the body wall of S. monotuberculatus belonged to dermis tissue. Starting from this perspective, crude collagen fibrils from dermis of S. monotuberculatus was isolated, and pepsin solubilized collagen was also obtained by hydrolyzing collagen telopeptides from crude collagen fibrils. Crude collagen fibrils and pepsin solubilized collagen were then acting as substrates, respectively, to identify dermis autoenzyme which had hydrolytic activity on dermis collagen. After that, ...
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isolation and characterization of collagen from the body wall of sea cucumber Stichopus monotuberculatus
Journal of Food Science, 2015Co-Authors: Ming Zhong, Ting Chen, Chunhua RenAbstract:To exploit a new collagen resource from the body wall of tropical sea cucumber, pepsin-solubilized collagen of Stichopus monotuberculatus (PSC-Sm) was isolated and characterized with UV-vis spectra, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), amino acid composition, enzyme-digested peptide maps, Fourier transform infrared spectroscopy (FTIR), maximum transition temperature (T-m), and solubilities. The maximum absorbance of PSC-Sm was exhibited at 218 nm in UV-vis spectra. The triple helical structure and activity of PSC-Sm could be indicated by FTIR. SDS-PAGE showed that the triple helix of PSC-Sm was formed as ((1))(3) by 3 (1) chain homologous with molecular weight of 137 kDa. The T-m of PSC-Sm and calf skin collagen (CSC) were 30.2 and 35.0 oC, respectively, which consistent with the result of FTIR that CSC contained more stable triple-helix than PSC-Sm. Peptide maps were different between PSC-Sm and CSC, indicating the differences in their amino acid compositions and sequences. The maximum and minimum solubilities of PSC-Sm were observed at pH 2.0 and 4.0, respectively. A sharp decrease in solubility appeared when NaCl concentration was between 3% and 5%. These results showed that collagen from S. monotuberculatus had the type I collagen characteristics and good thermal stability, and therefore, it could be used as an alternative resource of collagen. Practical Application The body wall of tropical sea cucumber Stichopus monotuberculatus is rich in collagen. Our present study provided the evidence for this collagen belonging to type I, and it could be an alternative resource of collagen because of good thermal stability. Meanwhile, this study provided a new insight of collagen, about the potential influence of amino acid composition on thermal stability, and understanding of the relationship between FTIR and T-m.
