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Marine Drugs Apr 2024Sea anemones are valuable for therapeutic research as a diversified source of bioactive molecules, due to their diverse bioactive molecules linked to predation and...
Sea anemones are valuable for therapeutic research as a diversified source of bioactive molecules, due to their diverse bioactive molecules linked to predation and defence mechanisms involving toxins and antimicrobial peptides. Acid extracts from tentacles and body were examined for antibacterial activity against Gram-positive, Gram-negative bacteria, and fungi. The peptide fractions showed interesting minimum inhibitory concentration (MIC) values (up to 0.125 µg/mL) against the tested pathogens. Further investigation and characterization of tentacle acid extracts with significant antimicrobial activity led to the purification of peptides through reverse phase chromatography on solid phase and HPLC. Broad-spectrum antimicrobial peptide activity was found in 40% acetonitrile fractions. The resulting peptides had a molecular mass of 2612.91 and 3934.827 Da and MIC ranging from 0.06 to 0.20 mg/mL. Sequencing revealed similarities to AMPs found in amphibians, fish, and Cnidaria, with anti-Gram+, Gram-, antifungal, candidacidal, anti-methicillin-resistant , carbapenemase-producing, vancomycin-resistant bacteria, and multi-drug resistant activity. Peptides 6.2 and 7.3, named Equinin A and B, respectively, were synthesized and evaluated in vitro towards the above-mentioned bacterial pathogens. Equinin B exerted interesting antibacterial activity (MIC and bactericidal concentrations of 1 mg/mL and 0.25 mg/mL, respectively) and gene organization supporting its potential in applied research.
Topics: Animals; Microbial Sensitivity Tests; Anti-Bacterial Agents; Antimicrobial Peptides; Sea Anemones; Gram-Positive Bacteria; Gram-Negative Bacteria; Anti-Infective Agents; Fungi
PubMed: 38667789
DOI: 10.3390/md22040172 -
Marine Drugs Mar 2024Five new biflorane-type diterpenoids, biofloranates E-I (-), and two new bicyclic diterpene glycosides, lemnaboursides H-I (-), along with the known lemnabourside, were...
Five new biflorane-type diterpenoids, biofloranates E-I (-), and two new bicyclic diterpene glycosides, lemnaboursides H-I (-), along with the known lemnabourside, were isolated from the South China Sea soft coral . Their chemical structures and stereochemistry were determined based on extensive spectroscopic methods, including time-dependent density functional theory (TDDFT) ECD calculations, as well as a comparison of them with the reported values. The antibacterial activities of the isolated compounds were evaluated against five pathogenic bacteria, and all of these diterpenes and diterpene glycosides showed antibacterial activities against and , with MICs ranging from 4 to 64 µg/mL. In addition, these compounds did not exhibit noticeable cytotoxicities on A549, Hela, and HepG2 cancer cell lines, at 20 μM.
Topics: Anthozoa; Diterpenes; Anti-Bacterial Agents; Animals; Glycosides; Humans; Microbial Sensitivity Tests; Staphylococcus aureus; Bacillus subtilis; HeLa Cells; Cell Line, Tumor; Hep G2 Cells; Molecular Structure; A549 Cells; China
PubMed: 38667774
DOI: 10.3390/md22040157 -
Marine Drugs Mar 2024Four undescribed sesquiterpenoids, lemneolemnanes A-D (-), have been isolated from the marine soft coral sp. The absolute configurations of the stereogenic carbons of -...
Four undescribed sesquiterpenoids, lemneolemnanes A-D (-), have been isolated from the marine soft coral sp. The absolute configurations of the stereogenic carbons of - were determined by single-crystal X-ray crystallographic analysis. Compounds and are epimers at C-3 and have an unusual skeleton with a formyl group on C-6. Compound possesses an uncommonly rearranged carbon skeleton, while has a 6/5/5 tricyclic system. Compound showed significant anti-Alzheimer's disease (AD) activity in a humanized AD pathological model.
Topics: Animals; Anthozoa; Sesquiterpenes; Caenorhabditis elegans; Crystallography, X-Ray; Alzheimer Disease; Disease Models, Animal; Humans; Molecular Structure
PubMed: 38667762
DOI: 10.3390/md22040145 -
PeerJ 2024Tropical coastal benthic communities will change in species composition and relative dominance due to global (e.g., increasing water temperature) and local (e.g.,...
Tropical coastal benthic communities will change in species composition and relative dominance due to global (e.g., increasing water temperature) and local (e.g., increasing terrestrial influence due to land-based activity) stressors. This study aimed to gain insight into possible trajectories of coastal benthic assemblages in Raja Ampat, Indonesia, by studying coral reefs at varying distances from human activities and marine lakes with high turbidity in three temperature categories (<31 °C, 31-32 °C, and >32 °C). The benthic community diversity and relative coverage of major benthic groups were quantified via replicate photo transects. The composition of benthic assemblages varied significantly among the reef and marine lake habitats. The marine lakes <31 °C contained hard coral, crustose coralline algae (CCA), and turf algae with coverages similar to those found in the coral reefs (17.4-18.8% hard coral, 3.5-26.3% CCA, and 15-15.5% turf algae, respectively), while the higher temperature marine lakes (31-32 °C and >32 °C) did not harbor hard coral or CCA. Benthic composition in the reefs was significantly influenced by geographic distance among sites but not by human activity or depth. Benthic composition in the marine lakes appeared to be structured by temperature, salinity, and degree of connection to the adjacent sea. Our results suggest that beyond a certain temperature (>31 °C), benthic communities shift away from coral dominance, but new outcomes of assemblages can be highly distinct, with a possible varied dominance of macroalgae, benthic cyanobacterial mats, or filter feeders such as bivalves and tubeworms. This study illustrates the possible use of marine lake model systems to gain insight into shifts in the benthic community structure of tropical coastal ecosystems if hard corals are no longer dominant.
Topics: Coral Reefs; Temperature; Animals; Ecosystem; Tropical Climate; Indonesia; Lakes; Biodiversity; Anthozoa
PubMed: 38666078
DOI: 10.7717/peerj.17132 -
Scientific Reports Apr 2024The Arabian Peninsula accounts for approximately 6% of the world's coral reefs. Some thrive in extreme environments of temperature and salinity. Using 51 Autonomous Reef...
The Arabian Peninsula accounts for approximately 6% of the world's coral reefs. Some thrive in extreme environments of temperature and salinity. Using 51 Autonomous Reef Monitoring Structure (ARMS), a standardized non-destructive monitoring device, we investigated the spatial patterns of coral reef cryptobenthic diversity in four ecoregions around the Arabian Peninsula and analyzed how geographical and/or environmental drivers shape those patterns. The mitochondrial cytochrome c oxidase subunit I (COI) gene was used to identify Amplicon Sequence Variants and assign taxonomy of the cryptobenthic organisms collected from the sessile and mobile fractions of each ARMS. Cryptobenthic communities sampled from the two ecoregions in the Red Sea showed to be more diverse than those inhabiting the Arabian (Persian) Gulf and the Gulf of Oman. Geographic distance revealed a stronger relationship with beta diversity in the Mantel partial correlation than environmental distance. However, the two mobile fractions (106-500 µm and 500-2000 µm) also had a significant correlation between environmental distance and beta diversity. In our study, dispersal limitations explained the beta diversity patterns in the selected reefs, supporting the neutral theory of ecology. Still, increasing differences in environmental variables (environmental filtering) also had an effect on the distribution patterns of assemblages inhabiting reefs within short geographic distances. The influence of geographical distance in the cryptofauna assemblages makes these relevant, yet usually ignored, communities in reef functioning vulnerable to large scale coastal development and should be considered in ecosystem management of such projects.
Topics: Coral Reefs; Biodiversity; Animals; Electron Transport Complex IV; Anthozoa; Indian Ocean
PubMed: 38664507
DOI: 10.1038/s41598-024-60336-8 -
The Science of the Total Environment Jun 2024The coral predators, crown-of-thorns starfish (COTS, Acanthaster spp.) remain a major cause of extensive and widespread coral loss in Indo-Pacific coral reefs. With... (Review)
Review
The coral predators, crown-of-thorns starfish (COTS, Acanthaster spp.) remain a major cause of extensive and widespread coral loss in Indo-Pacific coral reefs. With increased phylogenetic understanding of these seastars, at least five species appear to be present across different regions. We compare the feeding ecology of these species. Where acroporid corals are prevalent, Acanthaster spp. often exhibit a preference for these corals, with Porites being least preferred, as seen in most species including Acanthaster planci in the northern Indian Ocean and Acanthaster cf. solaris in the west Pacific. In the eastern Pacific, where Acropora is largely absent, Acanthaster cf. ellisii prey on a range of coral species, including Porites. Coral predation by COTS is influenced by several factors including food availability, coral nutritional value, protective crustaceans and coral defenses, with differences in feeding ecology and behaviour emerging across the different COTS species. Feeding behaviour of COTS can act to increase coral species richness by reducing the dominance of fast-growing species. In outbreaking populations, COTS impacts reef systems by reducing live coral cover, eroding reef complexity and causing shifts in reef trophic structure. Where data are available, we synthesise and contrast the feeding preferences and foraging behaviour of Acanthaster species, and their impact on coral assemblages across the different species and regions. For areas where focal predation on Acropora occurs, also the fastest growing coral with the greatest recovery potential following mass mortality events, the combination of climate change and COTS outbreaks presents an imminent threat to coral reefs. This is exacerbated by the dietary flexibility of Acanthaster species. The impacts of heatwaves, COTS and other stressors are creating a negative feedback loop accelerating coral reef decline.
Topics: Animals; Coral Reefs; Starfish; Anthozoa; Feeding Behavior; Indian Ocean; Pacific Ocean; Predatory Behavior; Food Chain
PubMed: 38663591
DOI: 10.1016/j.scitotenv.2024.172691 -
PloS One 2024Resilience-based management is essential to protect ecosystems in the Anthropocene. Unlike large-scale climate threats to Great Barrier Reef (GBR) corals, outbreaks of...
Resilience-based management is essential to protect ecosystems in the Anthropocene. Unlike large-scale climate threats to Great Barrier Reef (GBR) corals, outbreaks of coral-eating crown-of-thorns starfish (COTS; Acanthaster cf. solaris) can be directly managed through targeted culling. Here, we evaluate the outcomes of a decade of strategic COTS management in suppressing outbreaks and protecting corals during the 4th COTS outbreak wave at reef and regional scales (sectors). We compare COTS density and coral cover dynamics during the 3rd and 4th outbreak waves. During the 4th outbreak wave, sectors that received limited to no culling had sustained COTS outbreaks causing significant coral losses. In contrast, in sectors that received timely and sufficient cull effort, coral cover increased substantially, and outbreaks were suppressed with COTS densities up to six-fold lower than in the 3rd outbreak wave. In the Townsville sector for example, despite exposure to comparable disturbance regimes during the 4th outbreak wave, effective outbreak suppression coincided with relative increases in sector-wide coral cover (44%), versus significant coral cover declines (37%) during the 3rd outbreak wave. Importantly, these estimated increases span entire sectors, not just reefs with active COTS control. Outbreaking reefs with higher levels of culling had net increases in coral cover, while the rate of coral loss was more than halved on reefs with lower levels of cull effort. Our results also indicate that outbreak wave progression to adjoining sectors has been delayed, probably via suppression of COTS larval supply. Our findings provide compelling evidence that proactive, targeted, and sustained COTS management can effectively suppress COTS outbreaks and deliver coral growth and recovery benefits at reef and sector-wide scales. The clear coral protection outcomes demonstrate the value of targeted manual culling as both a scalable intervention to mitigate COTS outbreaks, and a potent resilience-based management tool to "buy time" for coral reefs, protecting reef ecosystem functions and biodiversity as the climate changes.
Topics: Animals; Starfish; Coral Reefs; Anthozoa; Conservation of Natural Resources; Ecosystem; Australia
PubMed: 38656948
DOI: 10.1371/journal.pone.0298073 -
Proceedings. Biological Sciences Apr 2024Bioluminescence is a widespread phenomenon that has evolved multiple times across the tree of life, converging among diverse fauna and habitat types. The ubiquity of...
Bioluminescence is a widespread phenomenon that has evolved multiple times across the tree of life, converging among diverse fauna and habitat types. The ubiquity of bioluminescence, particularly in marine environments where it is commonly used for communication and defense, highlights the adaptive value of this trait, though the evolutionary origins and timing of emergence remain elusive for a majority of luminous organisms. Anthozoan cnidarians are a diverse group of animals with numerous bioluminescent species found throughout the world's oceans, from shallow waters to the light-limited deep sea where bioluminescence is particularly prominent. This study documents the presence of bioluminescent Anthozoa across depth and explores the diversity and evolutionary origins of bioluminescence among Octocorallia-a major anthozoan group of marine luminous organisms. Using a phylogenomic approach and ancestral state reconstruction, we provide evidence for a single origin of bioluminescence in Octocorallia and infer the age of occurrence to around the Cambrian era, approximately 540 Ma-setting a new record for the earliest timing of emergence of bioluminescence in the marine environment. Our results further suggest this trait was largely maintained in descendants of a deep-water ancestor and bioluminescent capabilities may have facilitated anthozoan diversification in the deep sea.
Topics: Animals; Biological Evolution; Anthozoa; Luminescence; Phylogeny
PubMed: 38654652
DOI: 10.1098/rspb.2023.2626 -
FEMS Microbiology Ecology Apr 2024Since their radiation in the Middle Triassic period ∼240 million years ago, stony corals have survived past climate fluctuations and five mass extinctions. Their... (Review)
Review
Since their radiation in the Middle Triassic period ∼240 million years ago, stony corals have survived past climate fluctuations and five mass extinctions. Their long-term survival underscores the inherent resilience of corals, particularly when considering the nutrient-poor marine environments in which they have thrived. However, coral bleaching has emerged as a global threat to coral survival, requiring rapid advancements in coral research to understand holobiont stress responses and allow for interventions before extensive bleaching occurs. This review encompasses the potential, as well as the limits, of multiomics data applications when applied to the coral holobiont. Synopses for how different omics tools have been applied to date and their current restrictions are discussed, in addition to ways these restrictions may be overcome, such as recruiting new technology to studies, utilizing novel bioinformatics approaches, and generally integrating omics data. Lastly, this review presents considerations for the design of holobiont multiomics studies to support lab-to-field advancements of coral stress marker monitoring systems. Although much of the bleaching mechanism has eluded investigation to date, multiomic studies have already produced key findings regarding the holobiont's stress response, and have the potential to advance the field further.
Topics: Anthozoa; Animals; Symbiosis; Genomics; Metabolomics; Stress, Physiological; Proteomics; Computational Biology; Multiomics
PubMed: 38653719
DOI: 10.1093/femsec/fiae058 -
PeerJ 2024, a prized resource in Japan, plays a vital role in traditional arts and fishing industries. Because of diminished stock due to overexploitation, ongoing efforts are...
BACKGROUND
, a prized resource in Japan, plays a vital role in traditional arts and fishing industries. Because of diminished stock due to overexploitation, ongoing efforts are focused on restoration through transplantation. This study aimed to enhance our understanding of the reproductive biology of these valuable corals and find more efficient methods for sex determination, which may significantly contribute to conservation initiatives.
METHODS
We used 12 three-month aquarium reared colony fragments, conducted histological analysis for maturity and sex verification, and performed transcriptome analysis via assembly and mapping using the transcriptome to explore gene expression differences between female and male .
RESULTS
Our histological observations enabled sex identification in 33% of incompletely mature samples. However, the sex of the remaining 67% of samples, classified as immature, could not be identified. RNA-seq yielded approximately 21-31 million short reads from 12 samples. assembly yielded 404,439 highly expressed transcripts. Among them, 855 showed significant differential expression, with 786 differentially expressed transcripts between females and males. Heatmap analysis highlighted 283 female-specific and 525 male-specific upregulated transcripts. Transcriptome assembly mapped to yielded 28,092 contigs, leading to the identification of 190 highly differentially expressed genes, with 113 upregulated exclusively in females and 70 upregulated exclusively in males. Blastp analysis provided putative protein annotations for 83 female and 72 male transcripts. Annotation analysis revealed that female biological processes were related to oocyte proliferation and reproduction, whereas those in males were associated with cell adhesion.
DISCUSSION
Transcriptome analysis revealed sex-specific gene upregulation in incompletely mature and shared transcripts with , providing insight into its gene expression patterns. This study highlights the importance of using both and reference-based assembly methods. Functional enrichment analysis showed that females exhibited enrichment in cell proliferation and reproduction pathways, while males exhibited enrichment in cell adhesion pathways. To the best of our knowledge, this is the first report on the gene expressions of each sex during the spawning season. Our findings offer valuable insights into the physiological ecology of incompletely mature red Japanese precious corals and suggest a method for identifying sex using various genes expressed in female and male individuals. In the future, techniques such as transplantation, artificial fertilization, and larval rearing may involve sex determination methods based on differences in gene expression to help conserve precious coral resources and ecosystems.
Topics: Animals; Female; Male; Anthozoa; Gametogenesis; Gene Expression Profiling; Japan; Transcriptome
PubMed: 38646482
DOI: 10.7717/peerj.17182