Search results for "Sponge"
showing 10 items of 296 documents
Biosilica
2012
Biomineralization, biosilicification in particular (i.e. the formation of biogenic silica, SiO(2)), has become an exciting source of inspiration for the development of novel bionic approaches following 'nature as model'. Siliceous sponges are unique among silica-forming organisms in their ability to catalyze silica formation using a specific enzyme termed silicatein. In this study, we review the present state of knowledge on silicatein-mediated 'biosilica' formation in marine demosponges, the involvement of further molecules in silica metabolism and their potential applications in nano-biotechnology and bio-medicine. While most forms of multicellular life have developed a calcium-based skel…
Protein synthesis of the sponge Geodia cydonium: characterization of the system.
1974
Abstract The ribosomal population of the sponge Geodia cydonium has been examined. The monosomes have a sedimentation constant of 80 S, the sizes of the subunits are approximately 60 S and 45 S respectively. The polyribosomes contain up to 40 ribosomal units. Cell free protein synthesizing systems (cell homogenate as well as reconstituted system) have been prepared and characterized with respect to Mg2+, KCI and ATP concentrations, temperature, pH and time course of the reaction. In the cell-free system and in the cellular system the protein biosynthesis is inhibited by chloramphenicol. It is not affected by cycloheximide.
Origin of the Metazoan Immune System: Identification of the Molecules and Their Functions in Sponges
2011
SYNOPSIS. During the evolutionary transition to Metazoa, cell-cell- as well as cell-matrix recognition molecules have been formed, which made a further step in evolution possible, the establishment of an immune system. Sponges [Porifera] represent the oldest still extant metazoan phylum and consequently testify to major features of the common metazoan ancestor, the Urmetazoa. Most studies with respect to evolution and phylogeny in sponges have been performed with the marine demosponges Suberites domuncula and Geodia cydonium. These animals possess effective defense systems against microbes and parasites which involve engulfment of bacteria into specific cells, but also signal transduction p…
Analysis of the Sponge [Porifera] Gene Repertoire: Implications for the Evolution of the Metazoan Body Plan
2003
Sponges [phylum Porifera] form the basis of the metazoan kingdom and represent the evolutionary earliest phylum still extant. Hence, as living fossils, they are the taxon closest related to the hypothetical ancestor of all Metazoa, the Urmetazoa. Until recently, it was still unclear whether sponges are provided with a defined body plan. Only after the cloning, expression and functional studies of characteristic metazoan genes, could it be demonstrated that these animals comprise the structural elements which allow the sponge cells to organize themselves according to a body plan. Adhesion molecules involved in cell—cell and cell—matrix interactions have been identified. Among the cell—cell a…
Origin of Insulin Receptor-Like Tyrosine Kinases in Marine Sponges
1999
One autapomorphic character restricted to all Metazoa including Porifera [sponges] is the existence of transmembrane receptor tyrosine kinases (RTKs). In this study we screened for molecules from one subfamily within the superfamily of the insulin receptors. The subfamily includes the insulin receptors (InsR), the insulin-like growth factor I receptors, and the InsR-related receptors--all found in vertebrates--as well as the InsR-homolog from Drosophila melanogaster. cDNAs encoding putative InsRs were isolated from the hexactinellid sponge Aphrocallistes vastus, the demosponge Suberites domuncula, and the calcareous sponge Sycon raphanus. Phylogenetic analyses of the catalytic domains of th…
Anti-inflammatory activity in selected Antarctic benthic organisms
2014
Antarctic benthos was prospected in search for anti-inflammatory activity in polar benthic invertebrates, in two different geographical areas: deep-bottoms of the Eastern Weddell Sea and shallow-waters of the South Shetland Islands. A total of 36 benthic algae and invertebrate species were selected to perform solubility tests in order to obtain extracts that were soluble at an innocuous ethanol concentration (0.2%) for cell culture, and further test them for anti-inflammatory activity. From these, ethanol extracts of ten species from five different phyla resulted suitable to be studied in cell macrophage cultures (RAW 264.7). Cytotoxicity (MTT method) and production of inflammatory mediator…
New 2-Methoxy Acetylenic Acids and Pyrazole Alkaloids from the Marine Sponge Cinachyrella sp.
2017
Three new 2-methoxy acetylenic acids (1–3) and a known derivative (4), in addition to three new natural pyrazole alkaloids (5–7) were isolated from an Indonesian marine sponge of the genus Cinachyrella. Compounds 5 and 6 have previously been reported as synthetic compounds. The structures of the new compounds were established on the basis of one- and two-dimensional NMR spectroscopy as well as by mass spectrometric data. The absolute configuration of the new acetylenic acid derivatives (1–3) was established by ECD spectroscopy. All isolated compounds were evaluated for their cytotoxicity against L5178Y mouse lymphoma cells. Compounds 1–4 exhibited strong activity with an IC50 value of 0.3 µ…
Induction of new metabolites from sponge-associated fungus Aspergillus carneus by OSMAC approach.
2018
Abstract A comparative study on the metabolic profile of the sponge-associated fungus Aspergillus carneus using the OSMAC approach was conducted. The fungal strain was fermented on three different media including solid rice medium with or without sea salt and modified Czapek medium. Three new natural products, isopropylchaetominine (1), isoterrelumamide A (2) and 5′-epi-averufanin (3), together with fourteen known compounds (4–17) were isolated. The structures of the new compounds were established by 1D and 2D NMR spectroscopic analysis as well as by HRESIMS. Compound 2 was only found when the fungus was cultivated on modified Czapek medium, whereas compounds 4, 7, 11, 12, and 14 were only …
Initiation of an Aquaculture of Sponges for the Sustainable Production of Bioactive Metabolites in Open Systems: Example, Geodia cydonium.
1999
Among Metazoa, sponges (phylum Porifera) are the richest source for different bioactive compounds. The availability of the raw material is, however, restricted. To obtain enough of the bioactive compounds for application in human therapy, sponges have to be cultured in in vitro systems. One technique for the establishment of a long-term cell culture from sponges has recently been elaborated. Here, we present a procedure to cultivate tissue samples from sponges in an open system. The species Geodia cydonium, which produces bioactive compounds, has been selected. Tissue samples of approximately 10 g were attached to the bottoms of cultivation trays. After 2 to 3 days, the tissue samples forme…
Iron Induces Proliferation and Morphogenesis in Primmorphs from the Marine SpongeSuberites domuncula
2002
Dissociated cells from marine demosponges retain their proliferation capacity if they are allowed to form special aggregates, the primmorphs. On the basis of incorporation studies and septin gene expression, we show that Fe3+ ions are required for the proliferation of cells in primmorphs from Suberites domuncula. In parallel, Fe3+ induced the expression of ferritin and strongly stimulated the synthesis of spicules. This result is supported by the finding that the enzymatic activity of silicatein, converting organosilicon to silicic acid, depends on Fe3+. Moreover, the expression of a scavenger receptor molecule, possibly involved in the morphology of spicules, depends on the presence of Fe3…