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1.
PeerJ ; 12: e17259, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699194

RESUMO

Iron (Fe) plays a fundamental role in coral symbiosis, supporting photosynthesis, respiration, and many important enzymatic reactions. However, the extent to which corals are limited by Fe and their metabolic responses to inorganic Fe enrichment remains to be understood. We used respirometry, variable chlorophyll fluorescence, and O2 microsensors to investigate the impact of increasing Fe(III) concentrations (20, 50, and 100 nM) on the photosynthetic capacity of two Mediterranean coral species, Cladocora caespitosa and Oculina patagonica. While the bioavailability of inorganic Fe can rapidly decrease, we nevertheless observed significant physiological effects at all Fe concentrations. In C. caespitosa, exposure to 50 nM Fe(III) increased rates of respiration and photosynthesis, while the relative electron transport rate (rETR(II)) decreased at higher Fe(III) exposure (100 nM). In contrast, O. patagonica reduced respiration, photosynthesis rates, and maximum PSII quantum yield (Fv/Fm) across all iron enrichments. Both corals exhibited increased hypoxia (<50 µmol O2 L-1) within their gastric cavity at night when exposed to 50 and 100 nM Fe(III), leading to increased polyp contraction time and reduced O2 exchange with the surrounding water. Our results indicate that C. caespitosa, but not O. patagonica, might be limited in Fe for achieving maximal photosynthetic efficiency. Understanding the multifaceted role of iron in corals' health and their response to environmental change is crucial for effective coral conservation.


Assuntos
Antozoários , Ferro , Oxigênio , Fotossíntese , Antozoários/efeitos dos fármacos , Antozoários/metabolismo , Animais , Fotossíntese/efeitos dos fármacos , Ferro/metabolismo , Oxigênio/metabolismo , Mar Mediterrâneo , Simbiose
2.
Invertebr Syst ; 382024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38744497

RESUMO

Despite the widespread use of integrative taxonomic approaches, many scleractinian coral genera and species remain grouped in polyphyletic families, classified as incertae sedis or simply understudied. Oculinidae Gray, 1847 represents a family for which many taxonomic questions remain unresolved, particularly those related to some of the current genera, such as Oculina Lamark, 1816 or recently removed genera, including Cladocora Ehrenberg, 1834 and Madrepora Linnaeus, 1758. Cladocora is currently assigned to the family Cladocoridae Milne Edwards & Haime, 1857 and a new family, Bathyporidae Kitahara, Capel, Zilberberg & Cairns, 2024, was recently raised to accommodate Madrepora . However, the name Bathyporidae is not valid because this was not formed on the basis of a type genus name. To resolve taxonomic questions related to these three genera, the evolutionary relationships are explored through phylogenetic analyses of 18 molecular markers. The results of these analyses support a close relationship between the species Oculina patagonica and Cladocora caespitosa , indicating that these may belong to the same family (and possibly genus), and highlighting the need for detailed revisions of Oculina and Cladocora . By contrast, a distant relationship is found between these two species and Madrepora oculata , with the overall evidence supporting the placement of Madrepora in the resurrected family Madreporidae Ehrenberg, 1834. This study advances our knowledge of coral systematics and highlights the need for a comprehensive review of the genera Oculina , Cladocora and Madrepora .


Assuntos
Antozoários , Filogenia , Animais , Antozoários/classificação , Especificidade da Espécie
3.
Phytochemistry ; 223: 114113, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38697241

RESUMO

Eleven undescribed cembrane-type diterpenoids, named litoamentenes A-K (1-11), were isolated from the soft coral Litophyton amentaceum collected from the South China Sea. Their structures were elucidated by extensive analysis of spectroscopic data, comparison with the literature data, single crystal X-ray diffraction, quantum chemical calculations and TDDFT-ECD calculations. This is the first systematic investigation of L. amentaceum. In particular, compounds 1-3 are cembrane-type norditerpenoids that lack isopropyl side chains. Compound 6 is a cembrane-type norditerpenoid without a methyl group at C-4, the first natural product identified with this carbon skeleton. Compounds 6, 9 and 10 showed modest cytotoxicity against several human cancer cell lines with IC50 values ranging from 3.99 to 14.56 µM.


Assuntos
Antozoários , Diterpenos , Ensaios de Seleção de Medicamentos Antitumorais , Antozoários/química , Diterpenos/química , Diterpenos/farmacologia , Diterpenos/isolamento & purificação , Animais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , China , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Modelos Moleculares
4.
Mar Drugs ; 22(5)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38786610

RESUMO

Octocoral of the genus Clavularia is a kind of marine invertebrate possessing abundant cytotoxic secondary metabolites, such as prostanoids and dolabellanes. In our continuous natural product study of C. spp., two previously undescribed prostanoids [clavulone I-15-one (1) and 12-O-deacetylclavulone I (2)] and eleven known analogs (3-13) were identified. The structures of these new compounds were elucidated based on analysis of their 1D and 2D NMR, HRESIMS, and IR data. Additionally, all tested prostanoids (1 and 3-13) showed potent cytotoxic activities against the human oral cancer cell line (Ca9-22). The major compound 3 showed cytotoxic activity against the Ca9-22 cells with the IC50 value of 2.11 ± 0.03 µg/mL, which echoes the cytotoxic effect of the coral extract. In addition, in silico tools were used to predict the possible effects of isolated compounds on human tumor cell lines and nitric oxide production, as well as the pharmacological potentials.


Assuntos
Antozoários , Antineoplásicos , Prostaglandinas , Humanos , Antozoários/química , Animais , Linhagem Celular Tumoral , Prostaglandinas/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Óxido Nítrico/metabolismo , Concentração Inibidora 50 , Organismos Aquáticos , Estrutura Molecular
5.
Phytochemistry ; 222: 114110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663824

RESUMO

Molecular networking strategy-based prioritization of the isolation of the rarely studied soft coral Sinularia tumulosa yielded 14 sesquiterpenes. These isolated constituents consisted of nine different types of carbon frameworks, namely asteriscane, humulane, capillosane, seco-asteriscane, guaiane, dumortane, cadinane, farnesane, and benzofarnesane. Among them, situmulosaols A-C (1, 3 and 4) were previously undescribed ones, whose structures with absolute configurations were established by the combination of extensive spectral data analyses, quantum mechanical-nuclear magnetic resonance and time-dependent density functional theory electronic circular dichroism calculations, the Snatzke's method, and the modified Mosher's method. Notably, situmulosaol C (4) was the second member of capillosane-type sesquiterpenes. The plausible biogenetic relationships of these skeletally different sesquiterpenes were proposed. All sesquiterpenoids were evaluated for their antibacterial, cytotoxic and anti-inflammatory effects. The bioassay results showed compound 14 exhibited significant antibacterial activities against a variety of fish and human pathogenic bacteria with MIC90 values ranging from 3.6 to 33.8 µg/mL. Moreover, moderate cytotoxic effects against HEL cells for components 13 and 14 and moderate inhibitory effect on lipopolysaccharide-induced inflammatory responses in RAW264.7 cells for substance 13 were also observed.


Assuntos
Antozoários , Sesquiterpenos , Antozoários/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Animais , Camundongos , Estrutura Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , China , Células RAW 264.7 , Testes de Sensibilidade Microbiana , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Relação Estrutura-Atividade , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga
6.
Mar Drugs ; 22(4)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38667774

RESUMO

Five new biflorane-type diterpenoids, biofloranates E-I (1-5), and two new bicyclic diterpene glycosides, lemnaboursides H-I (6-7), along with the known lemnabourside, were isolated from the South China Sea soft coral Lemnalia bournei. 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 Staphylococcus aureus and Bacillus subtilis, 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.


Assuntos
Antozoários , Antibacterianos , Bacillus subtilis , Diterpenos , Glicosídeos , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Antozoários/química , Diterpenos/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Animais , Glicosídeos/farmacologia , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Staphylococcus aureus/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Células HeLa , Linhagem Celular Tumoral , Células Hep G2 , Estrutura Molecular , Células A549 , China
7.
PeerJ ; 12: e17037, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38436029

RESUMO

Clonal organisms like reef building corals exhibit a wide variety of colony morphologies and geometric shapes which can have many physiological and ecological implications. Colony geometry can dictate the relationship between dimensions of volume, surface area, and length, and their associated growth parameters. For calcifying organisms, there is the added dimension of two distinct components of growth, biomass production and calcification. For reef building coral, basic geometric shapes can be used to model the inherent mathematical relationships between various growth parameters and how colony geometry determines which relationships are size-dependent or size-independent. Coral linear extension rates have traditionally been assumed to be size-independent. However, even with a constant calcification rate, extension rates can vary as a function of colony size by virtue of its geometry. Whether the ratio between mass and surface area remains constant or changes with colony size is the determining factor. For some geometric shapes, the coupling of biomass production (proportional to surface area productivity) and calcification (proportional to volume) can cause one aspect of growth to geometrically constrain the other. The nature of this relationship contributes to a species' life history strategy and has important ecological implications. At one extreme, thin diameter branching corals can maximize growth in surface area and resource acquisition potential, but this geometry requires high biomass production to cover the fast growth in surface area. At the other extreme, growth in large, hemispheroidal corals can be constrained by calcification. These corals grow surface area relatively slowly, thereby retaining a surplus capacity for biomass production which can be allocated towards other anabolic processes. For hemispheroidal corals, the rate of surface area growth rapidly decreases as colony size increases. This ontogenetic relationship underlies the success of microfragmentation used to accelerate restoration of coral cover. However, ontogenetic changes in surface area productivity only applies to certain coral geometries where surface area to volume ratios decrease with colony size.


Assuntos
Antozoários , Calcinose , Características de História de Vida , Animais , Calcificação Fisiológica , Biomassa
8.
Mar Drugs ; 22(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38535455

RESUMO

Extensive research has been conducted on the isolation and study of bioactive compounds derived from marine sources. Several natural products have demonstrated potential as inducers of apoptosis and are currently under investigation in clinical trials. These marine-derived compounds selectively interact with extrinsic and intrinsic apoptotic pathways using a variety of molecular mechanisms, resulting in cell shrinkage, chromatin condensation, cytoplasmic blebs, apoptotic bodies, and phagocytosis by adjacent parenchymal cells, neoplastic cells, or macrophages. Numerous marine-derived compounds are currently undergoing rigorous examination for their potential application in cancer therapy. This review examines a total of 21 marine-derived compounds, along with their synthetic derivatives, sourced from marine organisms such as sponges, corals, tunicates, mollusks, ascidians, algae, cyanobacteria, fungi, and actinobacteria. These compounds are currently undergoing preclinical and clinical trials to evaluate their potential as apoptosis inducers for the treatment of different types of cancer. This review further examined the compound's properties and mode of action, preclinical investigations, clinical trial studies on single or combination therapy, and the prospective development of marine-derived anticancer therapies.


Assuntos
Actinobacteria , Antozoários , Antineoplásicos , Neoplasias , Animais , Estudos Prospectivos , Ensaios Clínicos como Assunto
9.
Sci Rep ; 14(1): 3369, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443414

RESUMO

Coral reef ecosystems supported by environmentally sensitive reef-building corals face serious threats from human activities. Our understanding of these reef threats is hampered by the lack of sufficiently sensitive coral environmental impact assessment systems. In this study, we established a platform for metabolomic analysis at the single-coral-polyp level using state-of-the-art mass spectrometry (probe electrospray ionization/tandem mass spectrometry; PESI/MS/MS) capable of fine-scale analysis. We analyzed the impact of the organic UV filter, benzophenone (BP), which has a negative impact on corals. We also analyzed ammonium and nitrate samples, which affect the environmental sensitivity of coral-zooxanthella (Symbiodiniaceae) holobionts, to provide new insights into coral biology with a focus on metabolites. The method established in this study breaks new ground by combining PESI/MS/MS with a technique for coral polyps that can control the presence or absence of zooxanthellae in corals, enabling functions of zooxanthellae to be assessed on a polyp-by-polyp basis for the first time. This system will clarify biological mechanisms of corals and will become an important model system for environmental impact assessment using marine organisms.


Assuntos
Antozoários , Dinoflagellida , Pólipos , Humanos , Animais , Ecossistema , Espectrometria de Massas em Tandem , Recifes de Corais
10.
Mar Environ Res ; 196: 106435, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38467089

RESUMO

Cnidarians may dominate benthic communities, as in the case of coral reefs that foster biodiversity and provide important ecosystem services. Polyps may feed by predating mesozooplantkon and large motile prey, but many species further obtain autotrophic nutrients from photosymbiosis. Anthropogenic disturbance, such as the rise of seawater temperature and turbidity, can lead to the loss of symbionts, causing bleaching. Prolonged periods of bleaching can induce mortality events over vast areas. Heterotrophy may allow bleached cnidarians to survive for long periods of time. We tested the reinforcement of heterotrophic feeding of bleached polyps of Exaiptasia diaphana fed with both small zooplantkon and large prey, in order to evaluate if heterotrophy allows this species to compensate the reduction of autotrophy. Conversely to expected, heterotrophy was higher in unbleached polyps (+54% mesozooplankton prey and +11% large prey). The increase of heterotrophic intake may not be always used as a strategy to compensate autotrophic depletion in bleached polyps. Such a resilience strategy might be more species-specific than expected.


Assuntos
Antozoários , Anêmonas-do-Mar , Animais , Ecossistema , Comportamento Predatório , Recifes de Corais , Simbiose
11.
Philos Trans R Soc Lond B Biol Sci ; 379(1901): 20230079, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38497261

RESUMO

Coral growth depends on the partnership between the animal hosts and their intracellular, photosynthetic dinoflagellate symbionts. In this study, we used the sea anemone Aiptasia, a laboratory model for coral biology, to investigate the poorly understood mechanisms that mediate symbiosis establishment and maintenance. We found that initial colonization of both adult polyps and larvae by a compatible algal strain was more effective when the algae were able to photosynthesize and that the long-term maintenance of the symbiosis also depended on photosynthesis. In the dark, algal cells were taken up into host gastrodermal cells and not rapidly expelled, but they seemed unable to reproduce and thus were gradually lost. When we used confocal microscopy to examine the interaction of larvae with two algal strains that cannot establish stable symbioses with Aiptasia, it appeared that both pre- and post-phagocytosis mechanisms were involved. With one strain, algae entered the gastric cavity but appeared to be completely excluded from the gastrodermal cells. With the other strain, small numbers of algae entered the gastrodermal cells but appeared unable to proliferate there and were slowly lost upon further incubation. We also asked if the exclusion of either incompatible strain could result simply from their cells' being too large for the host cells to accommodate. However, the size distributions of the compatible and incompatible strains overlapped extensively. Moreover, examination of macerates confirmed earlier reports that individual gastrodermal cells could expand to accommodate multiple algal cells. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.


Assuntos
Antozoários , Dinoflagellida , Anêmonas-do-Mar , Animais , Simbiose , Fotossíntese , Larva
12.
Environ Microbiol Rep ; 16(2): e13236, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38444282

RESUMO

Corals engage in symbioses with micro-organisms that provide nutrients and protect the host. Where the prokaryotic microbes perform their symbiotic functions within a coral is, however, poorly understood. Here, we studied the tissue-specific microbiota of the coral Corallium rubrum by dissecting its tissues from the skeleton and separating the white polyps from the red-coloured coenenchyme, followed by 16S rRNA gene metabarcoding of the three fractions. Dissection was facilitated by incubating coral fragments in RNAlater, which caused tissues to detach from the skeleton. Our results show compartmentalisation of the microbiota. Specifically, Endozoicomonas, Parcubacteria and a Gammaproteobacteria were primarily located in polyps, whereas Nitrincolaceae and one Spirochaeta phylotype were found mainly in the coenenchyme. The skeleton-associated microbiota was distinct from the microbiota in the tissues. Given the difference in tissue colour and microbiota of the polyps and coenenchyme, we analysed the microbiota of three colormorphs of C. rubrum (red, pink, white), finding that the main difference was a very low abundance of Spirochaeta in white colormorphs. While the functions of C. rubrum's symbionts are unknown, their localisation within the colony suggests that microhabitats exist, and the presence of Spirochaeta appears to be linked to the colour of C. rubrum.


Assuntos
Antozoários , Gammaproteobacteria , Animais , RNA Ribossômico 16S/genética , Bactérias/genética , Células Procarióticas , Gammaproteobacteria/genética
13.
Sci Total Environ ; 918: 170651, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38320710

RESUMO

Microplastic pollution is an increasing threat to coral reefs, which are already strongly challenged by climate change-related heat stress. Although it is known that scleractinian corals can ingest microplastic, little is known about their egestion and how microplastic exposure may impair corals at physiological and cellular levels. In addition, the effects of microplastic pollution at current environmental concentration have been little investigated to date, particularly in corals already impacted by heat stress. In this study, the combined effects of these environmental threats on Pocillopora damicornis were investigated from a physical and cellular perspective. Colonies were exposed to three concentrations of polyethylene microplastic beads (no microplastic beads: [No MP], 1 mg/L: [Low MP]; 10 mg/L: [High MP]), and two different temperatures (25 °C and 30 °C) for 72 h. No visual signs of stress in corals, such as abnormal mucus production and polyp extroflection, were recorded. At [Low MP], beads adhered to colonies were ingested but were also egested. Moreover, thermally stressed colonies showed a lower adhesion and higher egestion of microplastic beads. Coral bleaching was observed with an increase in temperature and microplastic bead concentration, as indicated by a general decrease in chlorophyll concentration and Symbiodiniaceae density. An increase in lipid peroxidation was measured in colonies exposed to [Low MP] and [High MP] and an up-regulation of stress response gene hsp70 was observed due to the synergistic interaction of both stressors. Overall, our findings showed that heat stress still represents the main threat to P. damicornis, while the effect of microplastics on coral health and physiology may be minor, especially at control temperature. However, microplastics could exacerbate the effect of thermal stress on cellular homeostasis, even at [Low MP]. While reducing ocean warming is critical for preserving coral reefs, effective management of emerging threats like microplastic pollution is equally essential.


Assuntos
Antozoários , Microplásticos , Animais , Microplásticos/toxicidade , Plásticos/toxicidade , Antozoários/fisiologia , Recifes de Corais , Resposta ao Choque Térmico
14.
Chem Biodivers ; 21(4): e202301993, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342755

RESUMO

A new alkaloids, aplysingoniopora A (1), and new configuration pregnane type steroid compound, 9,17-α-pregn-1,4,20-en-3-one (2), and two known pregnane type steroid compounds (3 and 4) were isolated from hydranth of Goniopora columna corals. The compounds structures and absolute configurations were determined by extensive spectroscopic analysis, MS data, single-crystal X-ray diffraction analysis and quantum chemical calculation. The anticancer effect of the compounds were explored in human non-small-cell lung cancer (NSCLC) A549 cell lines. As the results, the compound 3 and 4 induces toxicity and has proliferation inhibitory effects on A549 cells (IC50=58.99 µM and 58.77 µM, respectively) in vitro.


Assuntos
Alcaloides , Antozoários , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Animais , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Alcaloides/farmacologia , Alcaloides/química , Esteroides/farmacologia , Esteroides/química , Pregnanos/farmacologia , Estrutura Molecular
15.
Chem Biodivers ; 21(4): e202400235, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412304

RESUMO

Over the last decades, soft corals have been proven a rich source of biologically active compounds, featuring a wide range of chemical structures. Herein, we investigated the chemistry of an alcyonarian of the genus Lemnalia (Neptheidae), specimens of which were collected from the coral reefs near Al Lith, on the south-west coast of Saudi Arabia. A series of chromatographic separations led to the isolation of 31 sesquiterpenes, featuring mainly the nardosinane and neolemnane carbon skeletons, among which three (13, 14 and 28) are new natural products. The metabolites isolated in sufficient amounts were evaluated in vitro in human tumor and non-cancerous cell lines for a number of biological activities, including their cytotoxic, anti-inflammatory, anti-angiogenic, and neuroprotective activities, as well as for their effect on androgen receptor (AR)-regulated transcription. Among the tested metabolites, compound 12 showed comparable neuroprotective activity to the positive control N-acetylcysteine, albeit at a 10-fold lower concentration.


Assuntos
Antozoários , Antineoplásicos , Sesquiterpenos , Animais , Humanos , Arábia Saudita , Oceano Índico , Sesquiterpenos/química , Antozoários/química , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo
16.
Antonie Van Leeuwenhoek ; 117(1): 45, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424217

RESUMO

Strain AA17T was isolated from an apparently healthy fragment of Montipora capitata coral from the reef surrounding Moku o Lo'e in Kane'ohe Bay, O'ahu, Hawai'i, USA, and was taxonomically evaluated using a polyphasic approach. Comparison of a partial 16S rRNA gene sequence found that strain AA17T shared the greatest similarity with Aestuariibacter halophilus JC2043T (96.6%), and phylogenies based on 16S rRNA gene sequences grouped strain AA17T with members of the Aliiglaciecola, Aestuariibacter, Lacimicrobium, Marisediminitalea, Planctobacterium, and Saliniradius genera. To more precisely infer the taxonomy of strain AA17T, a phylogenomic analysis was conducted and indicated that strain AA17T formed a monophyletic clade with A. halophilus JC2043T, divergent from Aestuariibacter salexigens JC2042T and other related genera. As a result of monophyly and multiple genomic metrics of genus demarcation, strain AA17T and A. halophilus JC2043T comprise a distinct genus for which the name Fluctibacter gen. nov. is proposed. Based on a polyphasic characterisation and identifying differences in genomic and taxonomic data, strain AA17T represents a novel species, for which the name Fluctibacter corallii sp. nov. is proposed. The type strain is AA17T (= LMG 32603 T = NCTC 14664T). This work also supports the reclassification of A. halophilus as Fluctibacter halophilus comb. nov., which is the type species of the Fluctibacter genus. Genomic analyses also support the reclassification of Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica.


Assuntos
Alteromonadaceae , Antozoários , Ácidos Graxos , Animais , Ácidos Graxos/análise , Havaí , Baías , RNA Ribossômico 16S/genética , Filogenia , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana
17.
Commun Biol ; 7(1): 246, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424314

RESUMO

Coral reefs, the largest bioconstruction on Earth, are formed by calcium carbonate skeletons of corals. Coral skeleton formation commonly referred to as calcification occurs in a specific compartment, the extracellular calcifying medium (ECM), located between the aboral ectoderm and the skeleton. Calcification models often assume a direct link between the surrounding seawater and the ECM. However, the ECM is separated from the seawater by several tissue layers and the cœlenteron, which contains the cœlenteric fluid found in both polyps and cœnosarc (tissue connecting the polyps). Symbiotic dinoflagellate-containing cells line the cœlenteron and their photosynthetic activity contributes to changes in the chemistry of the cœlenteric fluid, particularly with respect to pH. The aim of our study is to compare cœlenteron pH between the cœnosarc and polyps and to compare areas of high or low dinoflagellate density based on tissue coloration. To achieve this, we use liquid ion exchange (LIX) pH microsensors to profile pH in the cœlenteron of polyps and the cœnosarc in different regions of the coral colony in light and darkness. We interpret our results in terms of what light and dark exposure means for proton gradients between the ECM and the coelenteron, and how this could affect calcification.


Assuntos
Antozoários , Calcinose , Animais , Concentração de Íons de Hidrogênio , Carbonato de Cálcio , Recifes de Corais , Água do Mar
18.
Toxins (Basel) ; 16(2)2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38393153

RESUMO

Cnidarians (corals, sea anemones, and jellyfish) produce toxins that play central roles in key ecological processes, including predation, defense, and competition, being the oldest extant venomous animal lineage. Cnidaria small cysteine-rich proteins (SCRiPs) were the first family of neurotoxins detected in stony corals, one of the ocean's most crucial foundation species. Yet, their molecular evolution remains poorly understood. Moreover, the lack of a clear classification system has hindered the establishment of an accurate and phylogenetically informed nomenclature. In this study, we extensively surveyed 117 genomes and 103 transcriptomes of cnidarians to identify orthologous SCRiP gene sequences. We annotated a total of 168 novel putative SCRiPs from over 36 species of stony corals and 12 species of sea anemones. Phylogenetic reconstruction identified four distinct SCRiP subfamilies, according to strict discrimination criteria based on well-supported monophyly with a high percentage of nucleotide and amino acids' identity. Although there is a high prevalence of purifying selection for most SCRiP subfamilies, with few positively selected sites detected, a subset of Acroporidae sequences is influenced by diversifying positive selection, suggesting potential neofunctionalizations related to the fine-tuning of toxin potency. We propose a new nomenclature classification system relying on the phylogenetic distribution and evolution of SCRiPs across Anthozoa, which will further assist future proteomic and functional research efforts.


Assuntos
Antozoários , Cnidários , Anêmonas-do-Mar , Animais , Antozoários/genética , Anêmonas-do-Mar/genética , Cnidários/genética , Neurotoxinas/genética , Cisteína/genética , Filogenia , Proteômica
19.
Mar Drugs ; 22(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38393066

RESUMO

The balance between bone-resorbing osteoclasts and bone-forming osteoblasts is essential for the process of bone remodeling. Excessive osteoclast differentiation plays a pivotal role in the pathogenesis of bone diseases such as rheumatoid arthritis and osteoporosis. In the present study, we examined whether 7,8-epoxy-11-sinulariolide acetate (Esa), a marine natural product present in soft coral Sinularia siaesensis, attenuates inflammation and osteoclastogenesis in vitro. The results indicated that Esa significantly inhibited lipopolysaccharide (LPS)-induced inflammation model of RAW264.7 cells and suppressed receptor activator for nuclear factor-κB ligand (RANKL)-triggered osteoclastogenesis. Esa significantly down-regulated the protein expression of iNOS, COX-2, and TNF-α by inhibiting the NF-κB/MAPK/PI3K pathways and reducing the release of reactive oxygen species (ROS) in RAW264.7 macrophages. Besides, Esa treatment significantly inhibited osteoclast differentiation and suppressed the expression of osteoclast-specific markers such as NFATC1, MMP-9, and CTSK proteins. These findings suggest that Esa may be a potential agent for the maintenance of bone homeostasis associated with inflammation.


Assuntos
Antozoários , Reabsorção Óssea , Diterpenos , Animais , Osteogênese , Fosfatidilinositol 3-Quinases/metabolismo , Diferenciação Celular , Osteoclastos , NF-kappa B/metabolismo , Inflamação/metabolismo , Antozoários/metabolismo , Ligante RANK/metabolismo , Fatores de Transcrição NFATC/metabolismo
20.
Chem Biodivers ; 21(3): e202301617, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38193652

RESUMO

In the current study, the actinomycetes associated with the red sea-derived soft coral Sarcophyton glaucum were investigated in terms of biological and chemical diversity. Four different media, M1, ISP2, Marine Agar (MA), and Actinomycete isolation agar (AIA) were used for the isolation of three strains of actinomycetes that were identified as Streptomyces sp. UR 25, Micromonospora sp. UR32 and Saccharomonospora sp. UR 19. LC-HRMS analysis was used to investigate the chemical diversity of the isolated actinobacteria. The LC-HRMS data were statistically processed using MetaboAnalyst 5.0 viz to differentiate the extract groups and determine the optimal growth culturing conditions. Multivariate data statistical analysis revealed that the Micromonospora sp. extract cultured on (MA) medium is the most distinctive extract in terms of chemical composition. While, the Streptomyces sp. UR 25 extracts are differ significantly from Micromonospora sp. UR32 and Saccharomonospora sp. UR 19. Biological investigation using in vitro cytotoxic assay for actinobacteria extracts revealed the prominent potentiality of the Streptomyces sp. UR 25 cultured on oligotrophic medium against human hepatoma (HepG2), human breast adenocarcinoma (MCF-7) and human colon adenocarcinoma (CACO2) cell lines (IC50 =3.3, 4.2 and 6.8 µg/mL, respectively). SwissTarget Prediction speculated that among the identified compounds, 16-deethyl, indanomycin (8) could have reasonable affinity on HDM2 active site. In this respect, molecular docking study was performed for compound (8) to reveal a substantial affinity on HDM2 active site. In addition, molecular dynamics simulations were carried out at 200 ns for the most active compound (8) compared to the co-crystallized inhibitor DIZ giving deeper information regarding their thermodynamic and dynamic properties as well.


Assuntos
Actinobacteria , Adenocarcinoma , Antozoários , Antineoplásicos , Neoplasias do Colo , Streptomyces , Animais , Humanos , Actinobacteria/química , Oceano Índico , Actinomyces , Ágar/metabolismo , Células CACO-2 , Simulação de Acoplamento Molecular , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo
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