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1.
ACS Omega ; 9(40): 41914-41922, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39398151

RESUMO

As exploration of ocean depths >1000 m is only possible by expensive remotely operated underwater vehicles, deep-sea invertebrates represent a largely untapped source of marine metabolites for potential applications in medicine. Our current study aims to investigate these deep-sea invertebrates in Ireland to discover new biological and chemical diversity. Here, we investigate the bubble gum coral, Paragorgia arborea, collected at 1500 m depth from Whittard canyon in the Northeastern Atlantic. This species was selected following chemical profiling and biological screening. The isolation and structure elucidation of the main metabolites yielded three new diterpenes, namely, miolenol (1) and epoxymiolenol (2) characterized by the rare bicyclo[7.2.0]undec-4-ene skeleton, and the xeniolide epoxycoraxeniolide A (3), together with five known diterpenes. The structures of the new compounds were identified through extensive NMR analysis with their absolute configurations assigned by comparison between experimental and TDDFT-calculated ECD. The eight compounds were screened for cytotoxicity and antimalarial activity, and none displayed noteworthy bioactivity.

2.
Curr Microbiol ; 81(11): 353, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264405

RESUMO

Microalgae are of great interest due to their ability to produce valuable compounds, such as pigments, omega-3 fatty acids, antioxidants, and antimicrobials. The dinoflagellate genus Amphidinium is particularly notable for its amphidinol-like compounds, which exhibit antibacterial and antifungal properties. This study utilized a two-stage cultivation method to grow Amphidinium carterae CCAP 1102/8 under varying conditions, such as blue LED light, increased salinity, and the addition of sodium carbonate or hydrogen peroxide. After cultivation, the biomass was extracted and fractionated using solid-phase extraction, yielding six fractions per treatment. These fractions were analyzed using Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS/MS) to identify their chemical components. Key amphidinol compounds (AM-B, AM-C, AM-22, and AM-A) were identified, with AM-B being the most abundant in Fraction 4, followed by AM-C. Fraction 5 also contained a significant amount of AM-C along with an unknown compound. Fraction 4 returned the highest antimicrobial activity against the pathogens Staphylococcus aureus, Enterococcus faecalis, and Candida albicans, with Minimal Biocidal Concentrations (MBCs) ranging from 1 to 512 µg/mL. Results indicate that the modulation of both amphidinol profile and fraction bioactivity can be induced by adjusting the cultivation parameters used to grow two-stage batch cultures of A. carterae.


Assuntos
Candida albicans , Dinoflagellida , Testes de Sensibilidade Microbiana , Dinoflagellida/química , Dinoflagellida/crescimento & desenvolvimento , Dinoflagellida/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Antibacterianos/farmacologia , Antibacterianos/química , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Cromatografia Líquida , Antifúngicos/farmacologia , Antifúngicos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anfidinóis
3.
Chem Biodivers ; 21(9): e202400549, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39177427

RESUMO

Sponges are recognized as promising sources for novel bioactive metabolites. Among them are terpenoid metabolites that constitute key biochemical defense mechanisms in several sponge taxa. Despite their significance, the genetic basis for terpenoid biosynthesis in sponges remains poorly understood. Dictyoceratida comprise demosponges well-known for their bioactive terpenoids. In this study, we explored the currently available genomic data for insights into the metabolic pathways of dictyoceratid terpenoids. We first identified prenyltransferase (PT) and terpene cyclase (TC) enzymes essential for the terpenoid biosynthetic processes in the terrestrial realm by analyzing available transcriptomic and genomic data of Dictyoceratida sponges and 10 other sponge species. All Dictyoceratida sponges displayed various PTs involved in either sesqui- or diterpene, steroid and carotenoid production. Additionally, it was possible to identify a potential candidate for a dictyoceratid sesterterpene PT. However, analogs of common terrestrial TCs were absent, suggesting the existence of a distinct or convergently evolved sponge-specific TC. Our study aims to contribute to the foundational understanding of terpene biosynthesis in sponges, unveiling the currently evident genetic components for terpenoid production in species not previously studied. Simultaneously, it aims to identify the known and unknown factors, as a starting point for biochemical and genetic investigations in sponge terpenoid production.


Assuntos
Genômica , Poríferos , Terpenos , Terpenos/metabolismo , Terpenos/química , Poríferos/metabolismo , Poríferos/genética , Animais , Dimetilaliltranstransferase/metabolismo , Dimetilaliltranstransferase/genética , Alquil e Aril Transferases/metabolismo , Alquil e Aril Transferases/genética , Filogenia
4.
Children (Basel) ; 11(8)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39201870

RESUMO

BACKGROUND: Robotic-assisted surgery (RAS) holds many theoretical advantages, especially in pediatric surgical procedures. However, most robotic systems are dedicated to adult surgery and are less suitable for smaller children. The Senhance® Surgical System (SSS®), providing 3 mm and 5 mm instruments, focuses on making RAS technically feasible for smaller children. This prospective observational study aims to assess whether RAS in pediatric patients using the SSS® is safe and feasible. METHODS AND RESULTS: A total of 42 children (aged 0-17 years, weight ≥ 10 kg) underwent a RAS procedure on the abdominal area using the SSS® between 2020 and 2023. The study group consisted of 20 male and 22 female individuals. The mean age was 10.7 years (range 0.8 to 17.8 years), with a mean body weight of 40.7 kg (range 10.1 to 117.3 kg). The 3-mm-sized instruments of the SSS® were used in 12 of the 42 children who underwent RAS. The RAS procedures were successfully completed in 90% of cases. The conversion rate to conventional laparoscopy was low (10%), and there were no conversions to open surgery. One of the 42 cases (2%) experienced intraoperative complications, whereas six children (14%) suffered from a postoperative complication. Overall, 86% of the patients had an uncomplicated postoperative course. CONCLUSIONS: The results of the current observational study demonstrate the safety and feasibility of utilizing the SSS® for abdominal pediatric RAS procedures. The study provides new fundamental information supporting the implementation of the SSS® in clinical practice in pediatric surgery.

5.
Phytochemistry ; 223: 114137, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734043

RESUMO

Exploring the chemical diversity present in cyanobacterial mats increasingly frequent in fresh and marine waters is imperative for both evaluating risks associated with these diverse biofilms and their potential for biodiscovery. During a project aimed at the study of the (eco)toxicity of benthic cyanobacteria blooming in some lakes of the West of Ireland, three previously undescribed ahp-cyclodepsipeptides micropeptin LOF941 (1), micropeptin LOF925 (2) and micropeptin LOF953 (3) were isolated from the Microcoleus autumnalis-dominated benthic cyanobacterial biofilm collected from the shore of Lough O'Flynn, Co. Roscommon, Ireland. Their structures remain consistent in their amino acid sequence with the presence of an unusual methionine, and differ by their exocyclic side chains. The planar structures of the previously undescribed micropeptins were elucidated by 1D and 2D NMR and HRESIMS analyses, and their 3D configurations assessed by ROESY NMR and Marfey's analyses. The three isolated compounds showed no cytotoxic effects and all three compounds were shown to exhibit antioxidant properties, with 1 showing the highest bioactivity. Additionally, several micropeptin analogues are proposed from the methanolic fraction of the biofilm extract by UHPLC-HRESIMS/MS analysis and molecular networking. Notably, the known cyanotoxins anatoxin-a and dihydroanatoxin-a were annotated in the molecular network therefore raising issues about the toxicity of this cyanobacterial mat.


Assuntos
Antioxidantes , Cianobactérias , Depsipeptídeos , Cianobactérias/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Irlanda , Depsipeptídeos/química , Depsipeptídeos/isolamento & purificação , Depsipeptídeos/farmacologia , Biofilmes/efeitos dos fármacos , Estrutura Molecular , Humanos
6.
J Nat Prod ; 87(4): 906-913, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38430199

RESUMO

The chemical diversity of annelids, particularly those belonging to the class Sipuncula, remains largely unexplored. However, as part of a Marine Biodiscovery program in Ireland, the peanut worm Phascolosoma granulatum emerged as a promising source of unique metabolites. The purification of the MeOH/CH2Cl2 extract of this species led to the isolation of six new linear guanidine amides, named phascolosomines A-F (1-6). NMR analysis allowed for the elucidation of their structures, all of which feature a terminal guanidine, central amide linkage, and a terminal isobutyl group. Notably, these guanidine amides were present in unusually high concentrations, comprising ∼3% of the dry mass of the organism. The primary concentration of the phascolosomines in the viscera is similar to that previously identified in linear amides from sipunculid worms and marine fireworms. The compounds from sipunculid worms have been hypothesized to be toxins, while those from fireworms are reported to be defensive irritants. However, screening of the newly isolated compounds for inhibitory bioactivity showed no significant inhibition in any of the assays conducted.


Assuntos
Amidas , Anelídeos , Guanidinas , Animais , Amidas/química , Amidas/farmacologia , Amidas/isolamento & purificação , Guanidina/química , Guanidina/farmacologia , Guanidinas/química , Guanidinas/farmacologia , Guanidinas/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Anelídeos/química
7.
Toxicon ; 240: 107631, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331106

RESUMO

Blooms of the dinoflagellate Ostreopsis cf. ovata are regularly associated with human intoxications that are attributed to ovatoxins (OVTXs), the main toxic compounds produced by this organism and close analogs to palytoxin (PlTX). Unlike for PlTX, information on OVTXs'toxicity are scarce due to the absence of commercial standards. Extracts from two cultures of Mediterranean strains of O. cf. ovata (MCCV54 and MCCV55), two fractions containing or not OVTXs (prepared from the MCCV54 extract) and OVTX-a and -d (isolated from the MCCV55 extract) were generated. These chemical samples and PlTX were tested on a panel of cell types from several organs and tissues (skin, intestine, lung, liver and nervous system). The MCCV55 extract, containing a 2-fold higher amount of OVTXs than MCCV54 extract, was shown to be more cytotoxic on all the cell lines and more prone to increase interleukin-8 (IL-8) release in keratinocytes. The fraction containing OVTXs was also cytotoxic on the cell lines tested but induced IL-8 release only in liver cells. Unexpectedly, the cell lines tested showed the same sensitivity to the fraction that does not contain OVTXs. With this fraction, a pro-inflammatory effect was shown both in lung and liver cells. The level of cytotoxicity was similar for OVTX-a and -d, except on intestinal and skin cells where a weak difference of toxicity was observed. Among the 3 toxins, only PlTX induced a pro-inflammatory effect mostly on keratinocytes. These results suggest that the ubiquitous Na+/K+ ATPase target of PlTX is likely shared with OVTX-a and -d, although the differences in pro-inflammatory effect must be explained by other mechanisms.


Assuntos
Acrilamidas , Venenos de Cnidários , Dinoflagellida , Toxinas de Poliéter , Humanos , Toxinas Marinhas/química , Interleucina-8 , Venenos de Cnidários/toxicidade , Dinoflagellida/química
8.
J Arthroplasty ; 39(8): 2100-2103, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38423259

RESUMO

BACKGROUND: Preoperative intra-articular corticosteroid injections to the hip joint increase the risk of periprosthetic joint infection (PJI) during primary total hip arthroplasty (THA). This study aimed to determine the relationship between preoperative timing of intra-articular corticosteroid injections and PJI risk following THA using data from a single-center hospital. METHODS: This single-center, retrospective cohort study included patients who underwent a THA between 2014 and 2020. Medical records were checked for intra-articular corticosteroid injections and PJI within 1 year of surgery. Patients were categorized into groups based on whether they received "no injection" or "injection 0 to 3 months," "3 to 6 months," and "> 6 months prior to THA." Hazard ratios (HRs) for these groups were calculated using multivariate Cox regression analysis, correcting for potential confounders, and presented with 95% confidence intervals [95% CIs]. RESULTS: In total, 4,507 patients (5,909 THAs) were identified. A total of 1,581 patients (27%) received an injection prior to THA. Without considering the timing factor, no increased risk for PJI following an intra-articular injection was noted (P = .19). Comparing the specified groups using multivariate analysis, corticosteroid injection within 3 months of THA showed an increased risk of PJI (HR 2.63, 95% CI 1.18 to 5.87, P = .018), but this effect was not observed for the "injection 3 to 6 months" group (HR 1.51, 95% CI 0.74 to 3.08, P = .264). CONCLUSIONS: Corticosteroid injections administered up to 3 months prior to THA increased the risk of PJI within 1 year after THA, with an HR of 2.63; however, injections between 3 and 6 months before surgery did not have a significantly higher infection rate.


Assuntos
Corticosteroides , Artroplastia de Quadril , Infecções Relacionadas à Prótese , Humanos , Artroplastia de Quadril/efeitos adversos , Injeções Intra-Articulares , Masculino , Feminino , Infecções Relacionadas à Prótese/etiologia , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Corticosteroides/administração & dosagem , Corticosteroides/efeitos adversos , Cuidados Pré-Operatórios/métodos , Articulação do Quadril/cirurgia , Fatores de Tempo , Idoso de 80 Anos ou mais
9.
Front Immunol ; 15: 1358459, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404576

RESUMO

Regulatory T lymphocytes expressing the transcription factor Foxp3 (Tregs) play an important role in the prevention of autoimmune diseases and other immunopathologies. Aberrations in Treg-mediated immunosuppression are therefore thought to be involved in the development of autoimmune pathologies, but few have been documented. Recent reports indicated a central role for Tregs developing during the neonatal period in the prevention of autoimmune pathology. We therefore investigated the development of Tregs in neonatal NOD mice, an important animal model for autoimmune type 1 diabetes. Surprisingly, we found that, as compared with seven other commonly studied inbred mouse strains, in neonatal NOD mice, exceptionally large proportions of developing Tregs express high levels of GITR and PD-1. The latter phenotype was previously associated with high Treg autoreactivity in C57BL/6 mice, which we here confirm for NOD animals. The proportions of newly developing GITRhighPD-1+ Tregs rapidly drop during the first week of age. A genome-wide genetic screen indicated the involvement of several diabetes susceptibility loci in this trait. Analysis of a congenic mouse strain confirmed that Idd5 contributes to the genetic control of GITRhighPD-1+ Treg development in neonates. Our data thus demonstrate an intriguing and paradoxical correlation between an idiosyncrasy in Treg development in NOD mice and their susceptibility to type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Camundongos , Animais , Diabetes Mellitus Tipo 1/genética , Camundongos Endogâmicos NOD , Linfócitos T Reguladores , Receptor de Morte Celular Programada 1/genética , Camundongos Endogâmicos C57BL , Fatores de Transcrição
10.
Nephrol Dial Transplant ; 39(3): 496-509, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37697719

RESUMO

BACKGROUND: The role of macrophages in the development of rhabdomyolysis-induced acute kidney injury (RM-AKI) has been established, but an in-depth understanding of the changes in the immune landscape could help to improve targeted strategies. Whereas senescence is usually associated with chronic kidney processes, we also wished to explore whether senescence could also occur in AKI and whether senolytics could act on immune cells. METHODS: Single-cell RNA sequencing was used in the murine glycerol-induced RM-AKI model to dissect the transcriptomic characteristics of CD45+ live cells sorted from kidneys 2 days after injury. Public datasets from murine AKI models were reanalysed to explore cellular senescence signature in tubular epithelial cells (TECs). A combination of senolytics (dasatinib and quercetin, DQ) was administered to mice exposed or not to RM-AKI. RESULTS: Unsupervised clustering of nearly 17 000 single-cell transcriptomes identified seven known immune cell clusters. Sub-clustering of the mononuclear phagocyte cells revealed nine distinct cell sub-populations differently modified with RM. One macrophage cluster was particularly interesting since it behaved as a critical node in a trajectory connecting one major histocompatibility complex class IIhigh (MHCIIhigh) cluster only present in Control to two MHCIIlow clusters only present in RM-AKI. This critical cluster expressed a senescence gene signature, that was very different from that of the TECs. Senolytic DQ treatment blocked the switch from a F4/80highCD11blow to F4/80lowCD11bhigh phenotype, which correlated with prolonged nephroprotection in RM-AKI. CONCLUSIONS: Single-cell RNA sequencing unmasked novel transitional macrophage subpopulation associated with RM-AKI characterized by the activation of cellular senescence processes. This work provides a proof-of-concept that senolytics nephroprotective effects may rely, at least in part, on subtle immune modulation.


Assuntos
Injúria Renal Aguda , Rabdomiólise , Camundongos , Animais , Senoterapia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/complicações , Rim , Rabdomiólise/complicações , Rabdomiólise/tratamento farmacológico , Análise de Sequência de RNA
11.
J Nat Prod ; 86(12): 2730-2738, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-38032127

RESUMO

In our continuing efforts to describe the biological and chemical diversity of sponges from Kimbe Bay, Papua New Guinea, the known 30-norlanostane saponin sarasinoside C1 (1) was identified along with six new analogues named sarasinosides C4, C5, C6, C7, C8, and C9 (2-7) from the sponge Melophlus sarasinorum. The structures of the new compounds were elucidated by analysis of 1D and 2D NMR and HRMS data, as well as comparison with literature data. All new compounds are characterized by the same tetraose moiety, ß-d-Xylp-(1→6)-ß-d-GlcNAcp-(1→2)-[ß-d-GalNAcp-(1→4)]-ß-d-Xylp, as described previously for sarasinoside C1, but differed in their aglycone moieties. When comparing NMR data of sarasinoside C8 with those of known analogues, a misassignment was identified in the configuration of the C-8/C-9 diol for the previously described sarasinoside R (8), and it has been corrected here using a combination of ROESY analysis and molecular modeling.


Assuntos
Poríferos , Saponinas , Animais , Poríferos/química , Papua Nova Guiné , Estrutura Molecular
12.
Harmful Algae ; 127: 102471, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37544671

RESUMO

Shellfish contamination with azaspiracids (AZA) is a major and recurrent problem for the Irish shellfish industry. Amphidoma languida, a small thecate dinoflagellate of the family Amphidomataceae, is widely distributed in Irish coastal waters and is one of the identified source species of azaspiracids. Irish and North Sea strains of Am. languida have been found to produce as major metabolites AZA-38 and -39 whose structures have only been provisionally elucidated by mass spectrometry and their toxic potential is currently unknown. In order to provide pure AZA-38 and -39 for subsequent structural and toxicological analyses, we present the first successful large-scale culture of Am. languida. A 180 L in house prototype bioreactor was used for culture growth and harvesting in semi-continuous mode for two months. Two different runs of the photobiorector with different light and pH setting showed the highest toxin yield at higher light intensity and slightly higher pH. AZA-38 and -39 cell quota were measured throughout the complete growth cycle with AZA-39 cell quota increasing in proportion to AZA-38 at late stationary to senescence phase. Over two experiments a total of 700 L of culture was harvested yielding 0.45 mg of pure AZA-39. The structure of AZA-39 was elucidated through NMR data analyses, which led to a revision of the structure proposed previously by mass spectrometry. While the spirotetrahydrofuran/tetrahydrofuran of rings A and B has been confirmed by NMR for AZA-39, a methyl is still present in position C-14 and the carboxylic acid chain is different from the structure proposed initially.


Assuntos
Dinoflagellida , Dinoflagellida/química , Fotobiorreatores , Espectrometria de Massas , Frutos do Mar/análise
13.
J Appl Microbiol ; 134(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37468451

RESUMO

AIM: A promising approach for the development of next-generation antimicrobials is to shift their target from causing bacterial death to inhibiting virulence. Marine sponges are an excellent potential source of bioactive anti-virulence molecules (AVM). We screened fractions prepared from 26 samples of Irish coastal sponges for anti-biofilm activity against clinically relevant pathogens. METHODS AND RESULTS: Fifteen fractions from eight sponge species inhibited biofilm of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), and/or Listeria monocytogenes without causing growth inhibition. Gas chromatograph/mass spectroscopy analyses of Mycale contarenii fractions revealed the presence of myristic acid and oleic acid. These fatty acids repressed transcription of the fibronectin-binding protein fnbA and fnbB genes and the polysaccharide intercellular adhesin icaADBC operon, which are required for MRSA and MSSA biofilm formation, respectively. CONCLUSIONS: This study illustrates the potential of AVM from Irish coastal sponges to specifically target bacterial virulence phenotypes, in this case, repression of biofilm formation via decreased transcription of biofilm-associated genes in MSSA and MRSA.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Poríferos , Infecções Estafilocócicas , Animais , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/genética , Antibacterianos/farmacologia , Ácidos Graxos/farmacologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Biofilmes , Testes de Sensibilidade Microbiana
14.
Sci Rep ; 13(1): 11589, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37463961

RESUMO

With climate projections questioning the future survival of stony corals and their dominance as tropical reef builders, it is critical to understand the adaptive capacity of corals to ongoing climate change. Biological mediation of the carbonate chemistry of the coral calcifying fluid is a fundamental component for assessing the response of corals to global threats. The Tara Pacific expedition (2016-2018) provided an opportunity to investigate calcification patterns in extant corals throughout the Pacific Ocean. Cores from colonies of the massive Porites and Diploastrea genera were collected from different environments to assess calcification parameters of long-lived reef-building corals. At the basin scale of the Pacific Ocean, we show that both genera systematically up-regulate their calcifying fluid pH and dissolved inorganic carbon to achieve efficient skeletal precipitation. However, while Porites corals increase the aragonite saturation state of the calcifying fluid (Ωcf) at higher temperatures to enhance their calcification capacity, Diploastrea show a steady homeostatic Ωcf across the Pacific temperature gradient. Thus, the extent to which Diploastrea responds to ocean warming and/or acidification is unclear, and it deserves further attention whether this is beneficial or detrimental to future survival of this coral genus.


Assuntos
Antozoários , Calcinose , Animais , Antozoários/fisiologia , Recifes de Corais , Regulação para Cima , Concentração de Íons de Hidrogênio , Carbonatos/metabolismo , Carbonato de Cálcio/metabolismo , Calcificação Fisiológica/fisiologia , Água do Mar
15.
Nat Commun ; 14(1): 3038, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37263999

RESUMO

Telomeres are environment-sensitive regulators of health and aging. Here,we present telomere DNA length analysis of two reef-building coral genera revealing that the long- and short-term water thermal regime is a key driver of between-colony variation across the Pacific Ocean. Notably, there are differences between the two studied genera. The telomere DNA lengths of the short-lived, more stress-sensitive Pocillopora spp. colonies were largely determined by seasonal temperature variation, whereas those of the long-lived, more stress-resistant Porites spp. colonies were insensitive to seasonal patterns, but rather influenced by past thermal anomalies. These results reveal marked differences in telomere DNA length regulation between two evolutionary distant coral genera exhibiting specific life-history traits. We propose that environmentally regulated mechanisms of telomere maintenance are linked to organismal performances, a matter of paramount importance considering the effects of climate change on health.


Assuntos
Antozoários , Animais , Antozoários/genética , Recifes de Corais , Temperatura , Estações do Ano , DNA/genética
16.
Nat Commun ; 14(1): 3039, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264002

RESUMO

Coral reefs are among the most diverse ecosystems on Earth. They support high biodiversity of multicellular organisms that strongly rely on associated microorganisms for health and nutrition. However, the extent of the coral reef microbiome diversity and its distribution at the oceanic basin-scale remains to be explored. Here, we systematically sampled 3 coral morphotypes, 2 fish species, and planktonic communities in 99 reefs from 32 islands across the Pacific Ocean, to assess reef microbiome composition and biogeography. We show a very large richness of reef microorganisms compared to other environments, which extrapolated to all fishes and corals of the Pacific, approximates the current estimated total prokaryotic diversity for the entire Earth. Microbial communities vary among and within the 3 animal biomes (coral, fish, plankton), and geographically. For corals, the cross-ocean patterns of diversity are different from those known for other multicellular organisms. Within each coral morphotype, community composition is always determined by geographic distance first, both at the island and across ocean scale, and then by environment. Our unprecedented sampling effort of coral reef microbiomes, as part of the Tara Pacific expedition, provides new insight into the global microbial diversity, the factors driving their distribution, and the biocomplexity of reef ecosystems.


Assuntos
Antozoários , Microbiota , Animais , Recifes de Corais , Oceano Pacífico , Biodiversidade , Peixes , Plâncton
17.
Nat Commun ; 14(1): 3037, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264015

RESUMO

Health and resilience of the coral holobiont depend on diverse bacterial communities often dominated by key marine symbionts of the Endozoicomonadaceae family. The factors controlling their distribution and their functional diversity remain, however, poorly known. Here, we study the ecology of Endozoicomonadaceae at an ocean basin-scale by sampling specimens from three coral genera (Pocillopora, Porites, Millepora) on 99 reefs from 32 islands across the Pacific Ocean. The analysis of 2447 metabarcoding and 270 metagenomic samples reveals that each coral genus harbored a distinct new species of Endozoicomonadaceae. These species are composed of nine lineages that have distinct biogeographic patterns. The most common one, found in Pocillopora, appears to be a globally distributed symbiont with distinct metabolic capabilities, including the synthesis of amino acids and vitamins not produced by the host. The other lineages are structured partly by the host genetic lineage in Pocillopora and mainly by the geographic location in Porites. Millepora is more rarely associated to Endozoicomonadaceae. Our results show that different coral genera exhibit distinct strategies of host-Endozoicomonadaceae associations that are defined at the bacteria lineage level.


Assuntos
Antozoários , Gammaproteobacteria , Animais , Antozoários/microbiologia , Oceano Pacífico , Ecologia , Bactérias , Recifes de Corais
18.
Sci Data ; 10(1): 324, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264023

RESUMO

The Tara Pacific expedition (2016-2018) sampled coral ecosystems around 32 islands in the Pacific Ocean and the ocean surface waters at 249 locations, resulting in the collection of nearly 58 000 samples. The expedition was designed to systematically study warm-water coral reefs and included the collection of corals, fish, plankton, and seawater samples for advanced biogeochemical, molecular, and imaging analysis. Here we provide a complete description of the sampling methodology, and we explain how to explore and access the different datasets generated by the expedition. Environmental context data were obtained from taxonomic registries, gazetteers, almanacs, climatologies, operational biogeochemical models, and satellite observations. The quality of the different environmental measures has been validated not only by various quality control steps, but also through a global analysis allowing the comparison with known environmental large-scale structures. Such publicly released datasets open the perspective to address a wide range of scientific questions.


Assuntos
Antozoários , Recifes de Corais , Animais , Ecossistema , Oceano Pacífico , Água do Mar
19.
Nat Commun ; 14(1): 3056, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264036

RESUMO

Heat waves are causing declines in coral reefs globally. Coral thermal responses depend on multiple, interacting drivers, such as past thermal exposure, endosymbiont community composition, and host genotype. This makes the understanding of their relative roles in adaptive and/or plastic responses crucial for anticipating impacts of future warming. Here, we extracted DNA and RNA from 102 Pocillopora colonies collected from 32 sites on 11 islands across the Pacific Ocean to characterize host-photosymbiont fidelity and to investigate patterns of gene expression across a historical thermal gradient. We report high host-photosymbiont fidelity and show that coral and microalgal gene expression respond to different drivers. Differences in photosymbiotic association had only weak impacts on host gene expression, which was more strongly correlated with the historical thermal environment, whereas, photosymbiont gene expression was largely determined by microalgal lineage. Overall, our results reveal a three-tiered strategy of thermal acclimatization in Pocillopora underpinned by host-photosymbiont specificity, host transcriptomic plasticity, and differential photosymbiotic association under extreme warming.


Assuntos
Antozoários , Transcriptoma , Animais , Oceano Pacífico , Transcriptoma/genética , Antozoários/genética , Aclimatação/genética , Recifes de Corais
20.
Sci Data ; 10(1): 326, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264047

RESUMO

Coral reef science is a fast-growing field propelled by the need to better understand coral health and resilience to devise strategies to slow reef loss resulting from environmental stresses. Key to coral resilience are the symbiotic interactions established within a complex holobiont, i.e. the multipartite assemblages comprising the coral host organism, endosymbiotic dinoflagellates, bacteria, archaea, fungi, and viruses. Tara Pacific is an ambitious project built upon the experience of previous Tara Oceans expeditions, and leveraging state-of-the-art sequencing technologies and analyses to dissect the biodiversity and biocomplexity of the coral holobiont screened across most archipelagos spread throughout the entire Pacific Ocean. Here we detail the Tara Pacific workflow for multi-omics data generation, from sample handling to nucleotide sequence data generation and deposition. This unique multidimensional framework also includes a large amount of concomitant metadata collected side-by-side that provide new assessments of coral reef biodiversity including micro-biodiversity and shape future investigations of coral reef dynamics and their fate in the Anthropocene.


Assuntos
Antozoários , Recifes de Corais , Animais , Biodiversidade , Ecossistema
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