Search Results (141)

The co-occurrence of rare terpenoid thiocyanates (R-SCN), structurally similar to their more common isothiocyanate isomers (R-NCS), poses an enigma: how does the accepted path, terpenyl cation R⁺ → R-NC → R-NCS, accommodate R-SCN? The mystery can now be rationalized by the consideration of three biosynthetic motifs: terpenoid carbocation (R⁺) capture by cyanoformate, NC-COOH (itself in equilibrium with NC⁻ and CO₂); co-localized rhodanese (a dual-function enzyme) that can both convert fugitive inorganic NC⁻ to thiocyanate ion, NCS⁻, and alkyl isonitriles to alkyl isothiocyanate (R-NC → R-NCS) and adventitious capture of the NCS⁻ by R⁺. The former two scenarios explain the preponderance of isothiocyanates, R-NCS, as products of a linear reaction path—the α-addition of S⁰ to R-NC—and the third scenario explains minor, less stable thiocyanates, R-SCN, as products of the adventitious capture of liberated NCS⁻ by the penultimate R⁺ precursor. DFT calculations support this proposal and eliminate other possibilities, e.g., the isomerization of R-NCS to R-SCN. Full article

In recent years, marine natural products have continued to serve as a pivotal resource for novel drug discovery. Globally, the number of studies focusing on Porifera has been on the rise, underscoring their considerable importance and research value. Marine sponges are prolific producers of a vast array of bioactive compounds, including terpenes, alkaloids, peptides, and numerous secondary metabolites. Over the past fifteen years, a substantial number of sponge-derived terpenes have been identified, exhibiting extensive structural diversity and notable biological activities. These terpenes have been isolated from marine sponges or their associated symbiotic microorganisms, with several demonstrating multifaceted biological activities, such as anti-inflammatory, antibacterial, cytotoxic, anticancer, and antioxidant properties. In this review, we summarize 997 novel terpene metabolites, detailing their structures, sources, and activities, from January 2009 to December 2024. The structural features and structure-activity relationship (SAR) of different types of terpenes are broadly analyzed and summarized. This systematic and comprehensive review will contribute to the summary of and speculation on the taxonomy, activity profiles, and SAR of terpenes and the development of sponge-derived terpenes as potential lead drugs. Full article

There are no reports of cancer in sponges, despite them having somatic cell turnover, long lifespans, and no specialized adaptive immune cells. In order to investigate whether sponges are cancer resistant, we exposed a species of sponge, Tethya wilhelma, to X-rays. We found that T. wilhelma can withstand 518 Gy of X-ray radiation. That is approximately 100 times the lethal dose for humans. A single high dose of X-rays did not induce cancer in T. wilhelma, providing the first experimental evidence of cancer resistance in the phylum Porifera. Following X-ray exposure, we found an overexpression of genes involved in DNA repair, signaling transduction pathways, and epithelial-to-mesenchymal transition. T. wilhelma has the highest level of radiation resistance that has yet been observed in animals that have sustained somatic cell turnover. This may make them an excellent model system for studying cancer resistance and developing new approaches for cancer prevention and treatment. Full article

The contribution of sponges to benthic communities in three areas of the Argentine continental shelf and slope (North, Central and South), between 34° and 55° S and between 47 and 551 m, is presented here. Sponges were recorded as components of the invertebrate by-catch in 51% of the studied sites (133 hauls). On average, sponges constituted 18.01% of the benthic community (47.91 kg/mn², in terms of density), reaching more than 90% of the by-catch and more than 500 kg/mn² at some particular sites. A total of 34 sponge taxa were recorded. Tedania spp., Clathria (C.) microxa and Callyspongidae (Siphonochalina fortis + Callyspongia sp.) were the only taxa shared among the three sampled areas. Sixty percent (60%) of the sponge species were recorded only at one or two sites. Full article

The waters around the western Antarctic Peninsula are experiencing fast warming due to global change, being among the most affected regions on the planet. This polar area is home to a large and rich community of benthic marine invertebrates, such as sponges, tunicates, corals, and many other animals. Among the sponges, the bright yellow Dendrilla antarctica is commonly known for using secondary diterpenoids as a defensive mechanism against local potential predators. From the dichloromethane extract of sponge samples from Deception Island collected in January 2023, we isolated a novel derivative with an unusual β-lactone diterpene skeleton here named dendrillolactone (1), along with seven previously described diterpenes, including deceptionin (2), a gracilane norditerpene (3), cadlinolide C (4), a glaciolane norditerpene (5), membranolide (6), aplysulphurin (7), and tetrahydroaplysulphurine-1 (8). Here, we also report our studies on the changes in the chemical arsenal of this sponge by slow temperature increase in aquaria experiments. Despite being a species capable of inhabiting volcanically active areas, with frequent water temperature fluctuations due to the existing fumaroles, the results show that diterpenes such as deceptionin, cadlinolide C, membranolide, and tetrahydroaplysulphurin-1 seem to be susceptible to the temperature increase, resulting in a trend to higher concentrations. However, temperatures above 4 °C severely affected sponge metabolism, causing its death much earlier than expected. Further research on the roles of these natural products in D. antarctica and their relationship to the sponge’s resilience to environmental changes should help to better understand the defensive mechanisms of Antarctic marine benthos in the context of global change. Full article

Stylasterid corals are known to be fundamental habitat-formers in both deep and shallow waters. Their tridimensional structure enhances habitat complexity by creating refuges for a variety of organisms and by acting as basibionts for many other invertebrates, including sponges. Porifera represent crucial components of marine benthic assemblages and, in Antarctica, they often dominate benthic communities. Here, we explore the sponge community associated with thanatocoenosis, mostly composed of dead stylasterid skeletons, collected along the Western and Northern edges of the Ross Sea continental shelf. Overall, 37 sponge species were identified from 278 fragments of the stylasterid Inferiolabiata labiata, of which 7 are first records for the Ross Sea, 1 is first record for Antarctic waters and 2 are proposed as new species. Despite the high biodiversity recorded in this and previous studies on Antarctic deep-sea communities, we are still far from capturing the true richness of Antarctic benthic assemblages. Long-term research programs designed to improve the knowledge of the deep-sea fauna inhabiting Antarctic waters are needed to support successful management and conservation plans, especially in this area, considered one of the main marine diversity hotspots worldwide. Full article

Chemical investigation of the Antarctic sponge Suberites sp. has previously led to the identification of new suberitane derivatives, some of which show bioactivity toward respiratory syncytial virus (RSV). Our ongoing NMR-guided investigation of new specimens of the sponge resulted in the isolation of five new analogs (1–5), previously reported suberitenones A–D (6–9), and oxaspirosuberitenone (10). Suberitenone K (1) was characterized as the 8-keto derivative of 6, while three new phenols, suberitandiol (2), abeosuberitandiol (3), and furanosuberitandiol (4), and the degraded sesterterpene norsuberitenone B (5) were also found. Compound 3 displays a ring contraction while 4 has a new dihydrofuran ring. Structural characterization was achieved by a combination of NMR, HR-MS, and X-ray diffraction (XRD). Moderate activity towards RSV was reported for 9 and the new metabolite 1, with IC₅₀ values of 15.0 μM and 39.8 μM, respectively. Full article

Alien species constitute one of the main threats to freshwater ecosystems, negatively impacting biodiversity, economy, and ecosystem services. Here, we use morphological and genetic data to show the presence of a new alien freshwater sponge in Europe, Rosulaspongilla rhadinaea, a Ponto-Caspian species which recently has been found in the fluvial port of Seville (Guadalquivir River, Spain). We also reviewed the mechanisms and adaptations of freshwater sponges for dispersal. The gemmule is the key structure for understanding their life history, evolution, and dispersal capacity, since their high salinity tolerance may have made possible the spreading of these sponges on the hulls of ocean-going ships that frequent freshwater ports. Once established, they are dispersed via river currents and intraregional boat traffic through the network of interconnected channels, which act as invasion corridors. Transport via phoresy attached to mobile animal vectors such as birds (especially migrating birds) has also been demonstrated in several sponge species. Gemmules may be attached on the feathers and scales, or even to be transported in the guts of these animals, followed by defecation of viable gemmules. Transport associated with other invasive freshwater species, such as mussels, cannot be ruled out. The scarcity of taxonomic studies of freshwater sponges in the Iberian Peninsula might explain why the species had not been recorded. Full article

The study of cryptic sponges can be challenging, as they are difficult to detect in the environment without the use of destructive methods. The permanence of mineral skeletal components of Porifera in sediments is therefore a tool that can provide support for a more comprehensive study of sponge fauna. In this context, sediments collected from four karst lakes in Ha Long Bay (Vietnam), plus two surrounding sea areas, were processed to extract spicules belonging to sponges with siliceous skeletons. From the morphology of the spicules, it was possible to trace the taxa of the sponges present in the area at that time or earlier. It was found that each lake had a sponge fauna composition characterized by different families and genera. Moreover, sponge taxa identified in the surrounding sea areas differed significantly from the ones inside of the neighboring lakes. In addition, it was possible to identify the presence of four sponge genera not yet recorded in the South China Sea area. Thus, the study of spicules trapped in sediments proved to be a useful tool for a comprehensive study of sponge fauna. Full article

The Notch signaling pathway plays a major role in embryological development and in the ongoing life processes of many animals. Its role is to provide cell-to-cell communication in which a Sender cell, bearing membrane-embedded ligands, instructs a Receiver cell, bearing membrane-embedded receptors, to adopt one of two available fates. Elucidating the evolution of this pathway is the topic of this paper, which uses an orthologs approach, providing a comprehensive basis for the study. Using BLAST searches, orthologs were identified for all the 49 components of the Notch signaling pathway. The historical time course of integration of these proteins, as the animals evolved, was elucidated. Insofar as cell-to-cell communication is of relevance only in multicellular animals, it is not surprising that the Notch system became functional only with the evolutionary appearance of Metazoa, the first multicellular animals. Porifera contributed a quarter of the Notch pathway proteins, the Cnidaria brought the total to one-half, but the system reached completion only when humans appeared. A literature search elucidated the roles of the Notch system’s components in modern descendants of the ortholog-contributing ancestors. A single protein, the protein tyrosine kinase (PTK) of the protozoan Ministeria vibrans, was identified as a possible pre-Metazoan ancestor of all three of the Notch pathway proteins, DLL, JAG, and NOTCH. A scenario for the evolution of the Notch signaling pathway is presented and described as the co-option of its components, clade by clade, in a repurposing of genes already present in ancestral unicellular organisms. Full article

Nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) inflammasomes are multiprotein signaling platforms that control the inflammatory response and coordinate antimicrobial defense. In the present study, the distribution of NLR, Caspase-1, and gasdermin (GSDM) homologues and their structural characteristics and evolutionary relationships were systematically analyzed in metazoa according to the genomes of species. In invertebrates, there were only NLRC and/or NLRD presented from sponge to amphioxus, and according to the evolutionary tree, NLR from sponge located in the most primitive position. Caspase-1 existed in some metazoan phyla (Brachiopoda, Ectoprocta, Arthropoda, Mollusca, Annelia, Nematoda, Platyelminthes, Coelenterate, and Porifera) and its activation sites were relatively conserved. The amino acid sequences and three-dimensional structures of N-terminal CARD/Death domain of NLR and Caspase-1 were similar in species from sponge to human. NLR and Caspase-1 co-existed in species of Brachiopoda, Mollusca, Annelia, Coelenterate, and Porifera. There was only GSDME or PJVK found in some phyla of invertebrates and their cleavage sites were conserved (DxxD). And it was predicted that the NLR inflammasome in inducing pyroptosis could occur in species of Brachiopoda, Mollusca, Annelia, and Coelenterate. These studies indicated that NLR inflammasome emerged early in sponges of metazoa, and NLR inflammasome in inducing pyroptosis first appeared in Coelenterate, suggesting that inflammasome and its mediated pyroptosis had existed in the early stage of metazoa, but they had been lost in many species during evolution. Full article

The taxonomic composition, structure, and distribution patterns of the macrobenthos associated with Corallium rubrum were studied along the coast of Taranto (Ionian Sea), together with the main features of their red coral population. Underwater video transects were performed by professional divers at three sites in correspondence with coralligenous formations at depths from 50 to 65 m. The results revealed a patchy distribution of red coral, with colonies predominantly located in cavities on sub-vertical cliffs and large boulders. Biometric analysis indicated that young colonies predominated at all sites, while older colonies were lacking, likely because of illegal harvesting. The lower density values were recorded at S1, while S2 and S3 presented higher values. A total of 76 taxa were recorded. S1, the shallowest site, showed a prevalence of calcareous algae, while S2 and S3 showed a greater abundance of filter-feeding invertebrates (Porifera and Cnidaria) with the highest presence of Porifera at S3. The results emphasize the heterogeneity of the macrobenthos together with the high vulnerability of the red coral population, highlighting the necessity of site-specific conservation strategies to contribute to the conservation and management of benthic ecosystems in the northern Ionian Sea. Full article

This study presents novel information on sponge (Porifera) colonization of artificial substrates in the framework of the LIFE EU Strong Sea Life Project, focusing on the northwestern Sardinian Sea (Western Mediterranean Sea). Five abandoned, lost, or discarded fishing gears (ALDFGs) of the local artisanal fishery from circum-seas of the Asinara Island Marine Protected Area (MPA) were focused. The composition, taxonomic richness, relative abundance, and lifestyle of sponge assemblages are reported. Taxonomic richness is notably high with 2 classes and 13 orders comprising 26 families, 36 genera, and 47 species of Porifera displaying miniaturized body size and dominant encrusting to massive/erect growth forms. New records at species level are reported for the MPA, the Sardinian Sea, and the Western Mediterranean Sea. The successful colonization of the recovered ghost fishing gears by sponges highlights that adaptive strategies of these basal metazoans support their ability to settle and persist on synthetic materials. This dataset contributes to the inventory of (i) recovered ALDFGs in MPAs, (ii) exogenous substrata as suitable substrata for sponge settlement, and (iii) species richness of an MPA and (iv) promotes the biodiversity assessment of the plastisphere in a global context of ocean pollution. Full article

We here report the purification of a novel member of the galectin family, the β-galactoside-binding lectin hRTL, from the marine sponge Chondrilla australiensis. The hRTL lectin is a tetrameric proto-type galectin with a subunit molecular weight of 15.5 kDa, consisting of 141 amino acids and sharing 92% primary sequence identity with the galectin CCL from the congeneric species C. caribensis. Transcriptome analysis allowed for the identification of additional sequences belonging to the same family, bringing the total number of hRTLs to six. Unlike most other galectins, hRTLs display a 23 amino acid-long signal peptide that, according to Erdman degradation, is post-translationally cleaved, leaving an N-terminal end devoid of acetylated modifications, unlike most other galectins. Moreover, two hRTLs display an internal insertion, which determines the presence of an unusual loop region that may have important functional implications. The characterization of the glycan-binding properties of hRTL revealed that it had high affinity towards TF-antigen, sialyl TF, and type-1 N-acetyl lactosamine with a Galβ1-3 structure. When administered to DLD-1 cells, a colorectal carcinoma cell line expressing mucin-associated TF-antigen, hRTL could induce glycan-dependent cytotoxicity. Full article