Sponge Research Articles

A geochemical and palynological study of lake sediments at Mboandong, Cameroon: chemical weathering and vegetation linked to Holocene palaeoclimate

Geochemical and palynological analyses of core samples from Mboandong, a crater lake in western Cameroon, provide a record of response to climate and vegetation change in West Africa over the last 7000 years. Three palaeoclimatic phases were identified: a humid phase (6800-5700 cal. BP), characterized by a humid and warm palaeoclimate; a drying phase (5700-2000 cal. BP) with a less humid palaeoclimate; finally, a seasonal phase (2000 cal. BP to present), characterized by a seasonally varied, mainly humid and warm palaeoclimate. Pollen components show swamp and humid rainforest taxa being gradually replaced by semi-deciduous, regrowth and non-tree taxa such as grasses (Poaceae). There is a suggestion of increasing aridity over the last 200 years. The sediments are primarily weathered deposits mixed with volcanic eruptive material, rather than detritus derived from the UCC (upper continental crust). Chemical Index of Alteration (CIA) values are mostly high (mean 90.65%) and indicate a variable but mostly humid palaeoclimate. CIA values are most likely influenced by climate, as well as by runoff and physical erosion. Bands of volcanic ash are associated with frequent freshwater sponge spicules and diatoms, probably due to increased availability of silica. Ca and Na depletion is probably linked with soil leaching, while K depletion and Mg enrichment were probably caused by chemical alteration. Humid intervals may have higher organic carbon content, whereas increased amounts of iron occur in potentially drier intervals. A greatly increased presence of oil palm pollen (Elaeis guineensis) is interpreted as evidence of cultivation after 1700 cal. BP.

Antifouling activity exhibited by pyrrolo compound isolated from marine sponge associated bacterium Halobacillus kuroshimensis SNSAB01 against barnacles

The increasing use of natural products from marine organisms and their synthetic analogs as antifouling agents is replacing chemical biocides due to their ecological compatibility. This study evaluated the antifouling potential of pyrrolo compound (PC) from the sponge-associated bacterium Halobacillus kuroshimensis against the barnacle Amphibalanus reticulatus larval survival, metamorphosis and settlement in the laboratory. The successful concentrations were also subjected to field based static immersion tests to study the efficacy of the PC extract on macrofouling settlement. Results showed decreased naupliar survival and affected larval metamorphosis in a dose-dependent manner, with varying sensitivity among developmental stages. Higher PC concentrations significantly reduced cyprid yield and settlement, with over 50% of cyprid larvae failing to settle at concentrations of 1300 μg/ml and above. Field experiments confirmed a steady decline in barnacle settlement on PC-treated coupons, with less than 50% settlement observed at concentrations of 500–2000 μg/ml over 50 days. The LC50/EC50 ratio for nauplius N-II was 1.11, with higher ratios observed in later stages and for the cypris (1.66), suggesting moderate toxicity and a narrow margin of safety. These ratios suggest barnacle settlement inhibition occurring through a toxic mechanism. The results demonstrate the compound's ability to disrupt barnacle settlement, but also raise concerns about its environmental impact (long-term usage), particularly the potential risks to non-target species before using the compound in real-world antifouling applications. Despite higher concentrations used compared to previous reports, PC shows potential as an effective natural antifouling compound.

Putative signaling pathways for contraction and its recovery from DEHP arrest in Hymeniacidon heliophila

With sessile habits, sponges (phylum Porifera) are susceptible to marine pollution impacts and recently microplastics were identified as one source of contamination. Microplastics have a physical impact on filtration rates and plastics additives such as di(2-ethylhexyl)phthalate (DEHP), a ubiquitous marine contaminant, were already identified in their tissues indicating bioaccumulation. However, few studies assessed the impacts of such compounds in its physiology. One verified effect of phthalate exposure is the arrest of the contraction cycles observed in the sponge Hymeniacidon heliophila. In this work, proteomics of DEHP exposed organisms of this species was performed to identify modifications in signaling pathways that could lead to this arrest and recovery. The results indicate that exposed organisms had different expressed 5HT receptors, associated to intracellular calcium signaling, the principal pathway to contraction animals. The Myosin Light-Chain Kinase (MLCK) pathway is detected only in exposed organisms as well as components linked to binding of organic cyclic compounds. Results show that for healing from DEHP exposure, H. heliophila may activate an alternative contraction signaling pathway, the MLCK pathway. These coordinate mechanisms could restore contractions in H. heliophila after acute exposure to DEHP. SynopsisResearch into the impact of microplastics on organisms uses animal models known to science such as mussels. In our work, we tested the effects of a plastic additive, DEHP, on the physiology of a much less studied marine organism: sponges.

Phage-induced disturbance of a marine sponge microbiome

BackgroundBacteriophages are known modulators of community composition and activity in environmental and host-associated microbiomes. However, the impact single phages have on bacterial community dynamics under viral predation, the extent and duration of their effect, are not completely understood. In this study, we combine morphological and genomic characterization of a novel marine phage, isolated from the Baltic sponge Halichondria panicea, and report on first attempts of controlled phage-manipulation of natural sponge-associated microbiomes.ResultsWe used culture-based and culture-independent (16S rRNA gene amplicon sequencing) methods to investigate bacterial community composition and dynamics in sponge microbiomes with and without the addition of phages. Upon application of a novel Maribacter specialist phage Panino under controlled conditions, we were able to detect community-wide shifts in the microbiome composition and load after 72 h. While bacterial community composition became more dissimilar over time in the presence of phages, species evenness and richness were maintained. Upon phage exposure, we observed the loss of several low-abundance constituent taxa of the resident microbiota, while other originally underrepresented taxa increased. Virulent phages likely induce community-wide disturbances, evident in changes in the total sponge microbial profile by specific elimination of constituent taxa, which leads to an increase in bacterial abundance of opportunistic taxa, such as the genera Vibrio, Pseudoalteromonas, and Photobacterium.ConclusionsOur findings suggest that sponge microbiome diversity and, by extension, its resilience depend on the maintenance of resident bacterial community members, irrespective of their abundance. Phage-induced disturbances can significantly alter community structure by promoting the growth of opportunistic bacteria like Vibrio and shifting the microbiome to a dysbiotic state. These insights highlight the role of bacteriophages in shaping microbiome dynamics and underscore the potential for phage application in managing bacterial community composition in marine host-associated environments.

Metagenomic insights and biosynthetic potential of Candidatus Entotheonella symbiont associated with Halichondria marine sponges.

Korea, being surrounded by the sea, provides a rich habitat for marine sponges, which have been a prolific source of bioactive natural products. Although a diverse array of structurally novel natural products has been isolated from Korean marine sponges, their biosynthetic origins remain largely unknown. To explore the biosynthetic potential of Korean marine sponges, we conducted metagenomic analyses of sponges inhabiting the East Sea of Korea. This analysis revealed a symbiotic association of Candidatus Entotheonella bacteria with Halichondria sponges. Here, we report a new chemically rich Entotheonella variant, which we named Ca. Entotheonella halido. Remarkably, this symbiont makes up 69% of the microbial community in the sponge Halichondira dokdoensis. Genome-resolved metagenomics enabled us to obtain a high-quality Ca. E. halido genome, which represents the largest (12 Mb) and highest quality among previously reported Entotheonella genomes. We also identified the biosynthetic gene cluster (BGC) of the known sponge-derived Halicylindramides from the Ca. E. halido genome, enabling us to determine their biosynthetic origin. This new symbiotic association expands the host diversity and biosynthetic potential of metabolically talented bacterial genus Ca. Entotheonella symbionts.IMPORTANCEOur study reports the discovery of a new bacterial symbiont Ca. Entotheonella halido associated with the Korean marine sponge Halichondria dokdoensis. Using genome-resolved metagenomics, we recovered a high-quality Ca. E. halido MAG (Metagenome-Assembled Genome), which represents the largest and most complete Ca. Entotheonella MAG reported to date. Pangenome and BGC network analyses revealed a remarkably high BGC diversity within the Ca. Entotheonella pangenome, with almost no overlapping BGCs between different MAGs. The cryptic and genetically unique BGCs present in the Ca. Entotheonella pangenome represents a promising source of new bioactive natural products.

The unique and enigmatic spirochete symbiont of latrunculid sponges.

Bacterial symbionts are critical members of many marine sponge holobionts. Some sponge-associated bacterial lineages, such as Poribacteria, sponge-associated unclassified lineage (SAUL), and Tethybacterales, appear to have broad-host ranges and associate with a diversity of sponge species, while others are more species-specific, having adapted to the niche environment of their host. Host-associated spirochete symbionts that are numerically dominant have been documented in several invertebrates including termites, starfish, and corals. However, dominant spirochete populations are rare in marine sponges, having thus far been observed only in Clathrina clathrus and various species within the Latrunculiidae family, where they are co-dominant alongside Tethybacterales symbionts. This study aimed to characterize these spirochetes and their potential role in the host sponge. Analysis of metagenome-assembled genomes from eight latrunculid sponges revealed that these unusual spirochetes are relatively recent symbionts and are phylogenetically distinct from other sponge-associated spirochetes. Functional comparative analysis suggests that the host sponge may have selected for these spirochetes due to their ability to produce terpenoids and/or possible structural contributions.IMPORTANCESouth African latrunculid sponges are host to co-dominant Tethybacterales and Spirochete symbionts. While the Tethybacterales are broad-host range symbionts, the spirochetes have not been reported as abundant in any other marine sponge except Clathrina clathrus. However, spirochetes are regularly the most dominant populations in marine corals and terrestrial invertebrates where they are predicted to serve as beneficial symbionts. Here, we interrogated eight metagenome-assembled genomes of the latrunculid-associated spirochetes and found that these symbionts are phylogenetically distinct from all invertebrate-associated spirochetes. The symbiosis between the spirochetes and their sponge host appears to have been established relatively recently.

Microbial communities associated with marine sponges from diverse geographic locations harbor biosynthetic novelty.

Marine sponges are a prolific source of biologically active small molecules, many of which originate from sponge-associated bacteria. Identifying the producing bacteria is a key step in developing sustainable routes for the production of these metabolites. To facilitate the required computational analyses, we developed MetaSing, a reproducible singularity-based pipeline for assembly, identification of high-quality metagenome-assembled genomes (MAGs), and analysis of biosynthetic gene clusters (BGCs) from metagenomic short-read data. We applied this pipeline to metagenomic sequencing data from 16 marine sponges collected from New Zealand, Tonga, and the Mediterranean Sea. This analysis yielded 643 MAGs representing 510 species. Of the 2,670 BGCs identified across all samples, 70.8% were linked to a MAG. Comparison of BGCs to those identified from previously sequenced bacteria revealed high biosynthetic novelty in variety of underexplored phyla, including Poribacteria, Acidobacteriota, and Dadabacteria. Alongside the observation that each sample contains unique biosynthetic potential, this holds great promise for natural product discovery and for furthering the understanding of different sponge holobionts.IMPORTANCEDiscovery of new chemical compounds such as natural products is a crucial endeavor to combat the increasing resistance to antibiotics and other drugs. This manuscript demonstrates that microbial communities associated with marine sponges investigated in this work encode the potential to produce novel chemistry. Lesser studied bacterial taxa that are often difficult to cultivate are particularly rich in potential.

Marine Smenospongia extract mitigated co-infection with Trichodina sp. and Flavobacterium columnare in Nile tilapia: insights into promoting growth performance, immune, antioxidant and autophagy defenses, and suppression of endoplasmic reticulum stress-related genes

Identifying novel natural sources from the marine environment with unique immunomodulatory and antioxidant efficacies is of interest in intensive fish farming. In this sense, marine sponge extract derived from Smenospongia (SS-extract) was tested for its potential anti-inflammatory, antioxidant and antimicrobial activities during the concurrent infection with Trichodina sp. and Flavobacterium columnare in Nile tilapia. A total of 625 Nile tilapia fingerlings were distributed into five groups: the control group (with no additives) and four groups fed the control diet fortified with SS-extract at 50, 100, 150, and 200 mg/kg, respectively, for 60 days. The parasitic challenge with Trichodina sp was done at the endpoint of the feeding trial and at 7 days post-infection (dpi); the fish were coinfected with F. columnare. A significant improvement in growth-related parameters of Nile tilapia was detected in the groups that received SS-extract at the levels of 150 and 200 mg/kg. The scavenging ability for free radicals (2,2′-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH)) was maximized with higher SS-extract supplementation levels. Simultaneously, the antioxidant defense of the Nile tilapia fed 150 and 200 mg/kg was augmented with a decline in oxidation-associated indicators [reactive oxygen species (ROS), hydrogen peroxide (H2O2), and malondialdehyde (MDA)]. The higher concentrations of SS-extract in the feed potentiated the immune response of Nile tilapia before infection and even after coinfection and was paralleled by a subsiding in the exaggerated inflammatory response after concurrent infection. Concurrently, the mRNA expression of autophagy-encountered genes (Atg5 and 12, LC3-II and BCLN1) had its highest expression in the fish fed the 200 mg/kg diet with the lowest expression of the mTOR gene in the same fish. The lowest infection intensity and rate and mucus score were displayed in fish fed 200 mg/kg SS-extract at 20 dpi. Interestingly, higher levels of SS-extract triggered antimicrobial peptides (upregulation of Hepcidin and β-defensin-1). In contrast, excessive expression of endoplasmic reticulum genes (atf4, JAK1, PERK, and eif2α) in the control infected group was downregulated by 200 mg/kg of SS-extract. The quantification of F. columnare indicated that columnaris coinfection severity displayed its lowest rate in the group supplemented with 200 mg/kg of SS-extract. In conclusion, a strategic siting based on fortification of the diet of Nile tilapia with SS-extract was elucidated to reinforce its immune and antioxidant defenses during a concurrent infection.

Design and Biofunctionalization of Cloud Sponge-Inspired Scaffolds for Enhanced Bone Cell Performance.

With the increasing age of our population, which is linked to a higher incidence of musculoskeletal diseases, there is a massive clinical need for bone implants. Porous scaffolds, usually offering a lower stiffness and allowing for the ingrowth of blood vessels and nerves, serve as an attractive alternative to conventional implants. Natural porous skeletons from marine sponges represent an array of evolutionarily optimized patterns, inspiring the design of biomaterials. In this study, cloud sponge-inspired scaffolds were designed and printed from a photocurable polymer, Clear Resin. These scaffolds were biofunctionalized by mussel-derived peptide MP-RGD, a recently developed peptide that contains a cyclic, bioactive RGD cell adhesion motif and catechol moieties, which provide the anchoring of the peptide to the surface. In in vitro cell culture assays with bone cells, significantly higher biocompatibility of three scaffolds, i.e., square, octagon, and hexagon cubes, in comparison to hollow and sphere inside cubes was shown. The performance of the cells regarding signaling was further enhanced by applying an MP-RGD coating. Consequently, these data demonstrate that both the structure of the scaffold and the coating contribute to the biocompatibility of the material. Three out of five MP-RGD-coated sponge-inspired scaffolds displayed superior biochemical properties and might guide material design for improved bone implants.

Targeting mitochondrial metabolism by the mitotoxin bromoxib in leukemia and lymphoma cells

Targeting mitochondrial metabolism represents a promising approach for cancer treatment. Here, we investigated the mitotoxic potential of the polybrominated diphenyl ether bromoxib, a natural compound isolated from the marine sponge Dysidea family. We could show that bromoxib comprised strong cytotoxicity in different leukemia and lymphoma cell lines (such as HL60, HPBALL, Jurkat, K562, KOPTK1, MOLT4, SUPB15 and Ramos), but also in solid tumor cell lines (such as glioblastoma cell lines SJ-GBM2 and TP365MG). Bromoxib activated the mitochondrial death pathway as evidenced by the rapid translocation of Bax to the mitochondria and the subsequent mitochondrial release of Smac. Accordingly, bromoxib-induced apoptosis was blocked in caspase 9 deficient Jurkat cells and Jurkat cells overexpressing the antiapoptotic protein Bcl-2. In addition, we could show that bromoxib functioned as an uncoupler of the electron transport chain with similar rapid kinetics as CCCP in terms of dissipation of the mitochondrial membrane potential (ΔΨm), processing of the dynamin-like GTPase OPA1 and subsequent fragmentation of mitochondria. Beyond that, bromoxib strongly abrogated ATP production via glycolysis as well as oxidative phosphorylation (OXPHOS) by targeting electron transport chain complexes II, III, and V (ATP-synthase) in Ramos lymphoma cells. Thus, bromoxib’s potential to act on both cytosolic glycolysis and mitochondrial respiration renders it a promising agent for the treatment of leukemia and lymphoma.

Archaeocytes in sponges: simple cells of complicated fate.

Archaeocytes are considered a key cell type in sponges (Porifera). They are believed to be multifunctional cells performing various functions, from nutrient digestion to acting as adult stem cells (ASCs). Thus, archaeocytes are mentioned in discussions on various aspects of sponge biology. As presumed ASCs of an early-diverged animal taxon, archaeocytes are of great fundamental interest for further progress in understanding tissue functioning in metazoans. However, the term 'archaeocyte' is rather ambiguous in its usage and understanding, and debates surrounding archaeocytes have persisted for over a century, reflecting the ongoing complexity of understanding their nature. This article presents a comprehensive revision of the archaeocyte concept, including both its historical development and biological features (i.e. taxonomic distribution, characteristics, and functions). The term 'archaeocyte' and its central aspects were introduced as early as the end of the 19th century based on data mainly from demosponges. Remarkably, despite the general lack of comparative and non-histological data, these early studies already regarded archaeocytes as the ASCs of sponges. These early views were readily inherited by subsequent studies, often without proper verification, shaping views on many aspects of sponge biology for more than a century. Taking into account all available data, we propose considering the archaeocytes as a cell type specific to the class Demospongiae. Clear homologues of archaeocytes are absent in other sponge classes. In demosponges, the term 'archaeocytes' refers to mesohyl cells that have an amoeboid shape, nucleolated nuclei, and non-specific inclusions in the cytoplasm. The absence of specific traits makes the archaeocytes a loosely defined and probably heterogeneous cell population, rendering the exhaustive characterisation of the 'true' archaeocyte population impossible. At the same time, the molecular characterisation of archaeocytes is only beginning to develop. Stemness and almost unlimited potency have always been at the core of the traditional archaeocyte concept. However, currently, the most consistent data on archaeocyte stem cell function come only from developing gemmules of freshwater sponges. For tissues of adult demosponges, the data favour a two-component stem cell system, in which archaeocytes may cooperate with another stem cell population, choanocytes. Simultaneously, cells with archaeocyte morphology function as macrophages in demosponges, participating in the food digestion cycle and immune defence. Such cells should be denoted with the more neutral term 'nucleolar amoebocytes', as the term 'archaeocyte' not only describes the morphology of a cell but also introduces the proposition of its stem nature. Thus, the future usage of the term 'archaeocyte' should be limited to cases where a cell is shown or at least presumed to be a stem cell.

Pullenvalenes E-H: Triterpenyl-Aminoglycosides from an Australian Soil-Derived Fungus, Clonostachys sp.

Chemical profiling of soil-derived microbes collected under the auspices of the Australian citizen science initiative Soils for Science detected two fungi, Clonostachys sp. S4S-07771A07 and Coccidiodes sp. S4S-14879B01, capable of producing pullenvalenes, a rare class of triterpene glycoside. Cultivation profiling followed by scaled up cultivation and fractionation of the former yielded the known pullenvalenes A-D (1-4) and the new analogues E-H (5-8), with structures secured by detailed spectroscopic analysis and biogenetic considerations. This study reveals that the pullenvalenes 1-8 are produced by several genera of fungi (Clonostachys, Coccidiodes and Talaromyces) recovered from different geographic locations and substrates. We also draw attention to structural and biosynthetic similarities with the known Red Sea sponge metabolites neviotines A-D (9-12) and abudinols A-B (13-14), prompting speculation that the latter may be products of sponge-associated fungi.

Stable dominance of parasitic dinoflagellates in Antarctic sponges.

Marine sponges are dominant components of Antarctic benthos and representative of the high endemism that characterizes this environment. All microbial groups are part of the Antarctic sponge holobionts, but microbial eukaryotes have been studied less, and their symbiotic role still needs to be better understood. Here, we characterize the dynamics of microbial eukaryotes associated with Antarctic sponges, focusing on dinoflagellates over three summer periods to better understand the members, interannual variations, and trophic and lifestyle strategies. The analysis revealed that dinoflagellates dominate microeukaryotic communities in Antarctic sponges. The results also showed significant differences in the diversity and composition of dinoflagellate communities associated with sponges compared to those in seawater. Antarctic sponges were dominated by a single dinoflagellate family, Syndiniales Dino-Group-I-Clade 1, which was present in high abundance in Antarctic sponges compared to seawater communities. Despite minor differences, the top microeukaryotic amplicon sequence variants (ASVs) showed no significant interannual abundance changes, indicating general temporal stability within the studied sponge species. Our findings highlight the abundance and importance of parasitic groups, particularly the classes Coccidiomorphea, Gregarinomorphea, and Ichthyosporea, with the exclusive dominance of Syndiniales Dino-Group-I-Clade 1 within sponges. The present study comprehensively characterizes the microbial eukaryotes associated with Antarctic sponges, showing a remarkable stability of parasitic dinoflagellates in Antarctic sponges. These findings underscore the significant role of parasites in these marine hosts, with implications for population dynamics of the microeukaryome and the holobiont response to a changing ocean.

Spongillidae (Porifera, Spongillidae) in the Subarctic of Western Siberia

When studying the zooperiphyton of reservoirs and watercourses in the Subarctic of Western Siberia, freshwater sponges were identified. The research was carried out in areas of the southern tundra and forested tundra belts, which in turn were conditionally divided into three zones: western, central and eastern. In total, the research covered 40 reservoirs and watercourses. Three species of sponges have been found: Spongilla lacustris, Ephydatia muelleri and Ephydatia fluviatilis. The most common species is S. lacustris, E. muelleri being less common, vs E. fluviatilis which occurs only occasionally. The maximum numbers of species and their occurrence were noted in forested tundra water bodies. Linear measurements and a dimensional analysis both of gemmules and elements of the skeleton of the sponges were carried out. A tendency was revealed to a decrease in size of the skeletal structures of the studied biological material in comparison with literature data.

Chemical Profile, Antioxidant and Antimicrobial Activity of Marine Sponge Species Combined with Multivariate Statistical Analyses: Desmapsamma anchorata, Dysidea etheria and Echinodictyum dendroides.

Marine sponges are valuable sources of bioactive compounds, which have attracted pharmacological interest. This study aimed to evaluate the chemical profile, antioxidant, and antibacterial activities of the species Desmapsamma anchorata, Dysidea etheria, and Echinodictyum dendroides. The chemical profile involved identifying and quantifying polyphenols, and antioxidant activity was evaluated using various methods. The antibacterial and modulatory activities were evaluated using microdilution against pathogenic strains. The extracts contained a low amount of polyphenols. In the antioxidant assays, the EACDa and EMDa extracts exhibited better inhibitory results. In the antibacterial evaluation, extracts presented MIC ≥1024 μg mL-1. The modulation of the extracts combined with antibiotics showed significant effects against the multiresistant bacterium Pseudomonas aeruginosa. This study contributes to the deepening of chemical and biological knowledge of sponge species. It indicates that their extracts can act as good modulators of bacterial resistance to aminoglycoside antibiotics, which requires further investigation into their mechanisms of action.

Temporal dynamics of the bacterial community structure and functions associated with marine sponges collected off Karah Island, Terengganu, Malaysia

The marine sponge microbiome has been investigated for decades, yet its temporal fluctuation/stability is poorly understood. This study aimed to describe the seasonal dynamics of the bacterial composition and predicted functions associated with two tropical marine sponge species (Aaptos suberitoides and Xestospongia testudinaria) collected off Karah Island, Malaysia, in the three seasons (dry season, pre- and post-monsoon season) using 16S rRNA gene amplicon sequencing and Functional Annotation of Prokaryotic Taxa (FAPROTAX). The bacterial taxonomic structures demonstrated divergences among A. suberitoides, X. testudinaria, and seawater, regardless of seasons. Chloroflexi, Proteobacteria, Cyanobacteria, Actinobacteriota, and Acidobacteriota comprised the core bacterial communities in two marine sponge species throughout the seasons, however, there were differences in bacterial composition between the two marine sponges. In addition, A. suberitoides was enriched with Dadabacteria, Spirochaetota, and Bdellovibrionota, whereas X. testudinaria abundantly harbored Poribacteria, PAUC34f, and Anck6. At the genus level, SAR202 clade and Candidatus Synechococcus spongiarum group dominated marine sponge samples throughout the year. Several genera, such as SAR202 clade, Candidatus Synechococcus spongiarum group, and Entotheonellaceae, were discovered only in marine sponge samples. Spirochaeta and Dadabacteriales displayed higher relative abundances in A. suberitoides, while Poribacteria and PAUC34f were more abundant in X. testudinaria. SAR202 clade was positively correlated with dissolved oxygen (DO), pH, phosphate, and ammonia in A. suberitoides. Likewise, Candidatus Synechococcus spongiarum group was negatively correlated with salinity and nitrate in X. testudinaria. Predicted functions by FAPROTAX annotated the phototrophic-related functions in both marine sponges, which might be attributed to a sponge-specific taxon Candidatus Synechococcus spongiarum group. The functions “predatory or exoparasitic” and “fermentation” were highly detected in A. suberitoides, which might be related to the bacterial genera Bdellovibrio and Spirochaeta, respectively. This study guides a deep understanding of the bacterial community structures associated with tropical marine sponges and their temporal behavior.

Anti-mycobacterial activity of secondary metabolites from marine sponge Agelas sp

Anti-mycobacterial activity of secondary metabolites from marine sponge Agelas sp

Bioassay-guided isolation and in Silico characterization of cytotoxic compounds from Hemimycale sp. Sponge targeting A549 lung cancer cells

Bioassay-guided fractionation approach led to identification of two novel compounds; (4-(hydroxymethyl)-3-methoxy-1H-pyrazol (1) and mycalene (2), alongside with four known metabolites; octadecane (3), hexatriacontane (4), 1-heneicosanol (5) and heptatriacontanoic acid (6) from the Red Sea marine sponge Hemimycale sp. The ethyl acetate fraction showed a noticeable cytotoxic activity against the lung cancer cell line (A549) with IC50 value of 75.54 µg/ mL. Structural elucidation was achieved using a combination of 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS). To elucidate the potential mechanism of action behind the cytotoxic effects against lung cancer, a multi-faceted approach combining in silico network pharmacology, experimental validation, and molecular docking studies were employed. Both compounds, designated as 1 and 2, demonstrated significant binding affinities to predicted target proteins, with docking scores of -4.789 and − 4.421 kcal/mol, respectively. These results lay the groundwork for further investigation into the therapeutic potential of these novel compounds from Hemimycale sp. as promising candidates for lung cancer treatment.

Paracoccus spongiarum sp. nov., isolated from the marine sponge, Phakellia elegans.

A facultative anaerobic Gram-negative bacterium, designated as strain 2205BS29-5T, was isolated from a marine sponge, Phakellia elegans, in Beomseom on Jeju Island, Republic of Korea, and taxonomically characterized. The cells were catalase and oxidase positive, non-motile, coccoid-rod shaped and capable of poly-β-hydroxybutyrate production. Growth was observed at 10-37 °C (optimum, 25 °C) and pH 5.0-8.0 (optimum, pH 7.0), and in the presence of 0-9% NaCl (w/v) (optimum, 3.0-4.0%). The major cellular fatty acids and respiratory quinone were identified as summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and Q-10, respectively. The major polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, four phosphoglycolipids, two unidentified amino lipids and eight unidentified lipids. The DNA G+C content was 67.8%. Strain 2205BS29-5T was most closely represented by Paracoccus amoyensis 11-3T and P. caeni MJ17T with 97.8 and 97.5% 16S rRNA gene sequence similarities, respectively. Phylogenetic analyses based on 16S rRNA genes and whole-genome sequences showed that strain 2205BS29-5T was affiliated with the genus Paracoccus. Genomic analysis showed that strain 2205BS29-5T could synthesize vitamin B family (folate and cobalamin) and ectoine. The average nucleotide identity and digital DNA-DNA hybridization values between strain 2205BS29-5T and P. amoyensis 11-3T were 77.1% and 18.8%, respectively, and with P. caeni MJ17T were 78.4 and 21.2%, respectively. Based on phylogenetic, chemotaxonomic and genome relatedness analyses, strain 2205BS29-5T represents a novel species of the genus Paracoccus, for which the name Paracoccus spongiarum sp. nov. is proposed. The type strain is 2205BS29-5T (=LMG 33062T =KACC 23240T).

Chemical and Biological Prospection of Marine Sponges Belonging to the Class Demospongiae: A Review.

Marine sponges belonging to the class Demospongiae have shown to be promising sources of bioactive compounds. This review aimed to compile studies on the biological activities and chemical components of sponge species from this class, highlighting the structure/activity relationship. Data collection was conducted using the Science Direct, PubMed, Scielo, Web of Science and Google Scholar databases, employing the following descriptors: antimicrobial marine sponges, antioxidant marine sponges, and biological activity of marine sponges. The inclusion criteria were: (1) publications from the year 2022 onwards; (2) written in English or Portuguese; and (3) that evaluated biological activities. Exclusion criteria included: (1) duplicate studies; (2) studies that were not within the scope; and (3) studies that did not evaluate biological activities. As a result of this survey, it was possible to isolate and identify 262 compounds from different metabolic classes, with terpenes, lipids, and alkaloids being highlighted. The extracts, fractions, and isolates were investigated for their antioxidant, antimicrobial, anti-inflammatory, and cytotoxic properties. The sponges demonstrated broad-spectrum antimicrobial potential and cytotoxic potential against various cancer cell lines. Based on data analysis, it is concluded that the studied compounds show promise for the development of drugs for microorganism control and cancer treatment, acting through different mechanisms of action.