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1.
Environ Microbiol ; 25(12): 3207-3224, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37732569

RESUMO

The sponge microbiome underpins host function through provision and recycling of essential nutrients in a nutrient poor environment. Genomic data suggest that carbohydrate degradation, carbon fixation, nitrogen metabolism, sulphur metabolism and supplementation of B-vitamins are central microbial functions. However, validation beyond the genomic potential of sponge symbiont pathways is rarely explored. To evaluate metagenomic predictions, we sequenced the metagenomes and metatranscriptomes of three common coral reef sponges: Ircinia ramosa, Ircinia microconulosa and Phyllospongia foliascens. Multiple carbohydrate active enzymes were expressed by Poribacteria, Bacteroidota and Cyanobacteria symbionts, suggesting these lineages have a central role in assimilating dissolved organic matter. Expression of entire pathways for carbon fixation and multiple sulphur compound transformations were observed in all sponges. Gene expression for anaerobic nitrogen metabolism (denitrification and nitrate reduction) were more common than aerobic metabolism (nitrification), where only the I. ramosa microbiome expressed the nitrification pathway. Finally, while expression of the biosynthetic pathways for B-vitamins was common, the expression of additional transporter genes was far more limited. Overall, we highlight consistencies and disparities between metagenomic and metatranscriptomic results when inferring microbial activity, while uncovering new microbial taxa that contribute to the health of their sponge host via nutrient exchange.


Assuntos
Cianobactérias , Microbiota , Poríferos , Animais , Filogenia , Cianobactérias/genética , Microbiota/genética , Vitaminas/metabolismo , Carboidratos , Simbiose
2.
Qual Health Res ; 30(5): 693-703, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31526106

RESUMO

The end-of-life trajectory of cancer patients in palliative care (PC) elicits an anticipatory grief (AG) process in family caregivers (FCs). Although widely recognized, AG lacks conceptual clarification. This study aims to qualitatively explore the experience of FCs of patients with terminal cancer to identify the core characteristics and the specific adaptive challenges related to AG in the context of end-of-life caregiving. Data were collected through in-depth semi-structured interviews conducted in a clinical sample of 26 FCs of cancer patients in PC. Findings from thematic analysis suggest that the AG experience is characterized by traumatic distress from being exposed to life-threatening conditions and the separation distress induced by loss anticipation and current relational losses, challenging the FCs to long-term emotional regulation effort demands. These results contribute to the conceptualization of AG and may inform intervention programs for the main challenges the FCs face when adjusting to loss during end-of-life caregiving.


Assuntos
Cuidadores , Neoplasias , Morte , Pesar , Humanos , Cuidados Paliativos
3.
Mol Ecol ; 27(14): 2956-2971, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29900626

RESUMO

Spatially adjacent habitats on coral reefs can represent highly distinct environments, often harbouring different coral communities. Yet, certain coral species thrive across divergent environments. It is unknown whether the forces of selection are sufficiently strong to overcome the counteracting effects of the typically high gene flow over short distances, and for local adaptation to occur. We screened the coral genome (using restriction site-associated sequencing) and characterized both the dinoflagellate photosymbiont- and tissue-associated prokaryote microbiomes (using metabarcoding) of a reef flat and slope population of the reef-building coral, Pocillopora damicornis, at two locations on Heron Island in the southern Great Barrier Reef. Reef flat and slope populations were separated by <100 m horizontally and ~5 m vertically, and the two study locations were separated by ~1 km. For the coral host, genetic divergence between habitats was much greater than between locations, suggesting limited gene flow between the flat and slope populations. Consistent with environmental selection, outlier loci primarily belonged to the conserved, minimal cellular stress response, likely reflecting adaptation to the different temperature and irradiance regimes on the reef flat and slope. The prokaryote community differed across both habitat and, to a lesser extent, location, whereas the dinoflagellate photosymbionts differed by habitat but not location. The observed intraspecific diversity associated with divergent habitats supports that environmental adaptation involves multiple members of the coral holobiont. Adaptive alleles or microbial associations present in coral populations from the environmentally variable reef flat may provide a source of adaptive variation for assisted evolution approaches, through assisted gene flow, artificial cross-breeding or probiotic inoculations, with the aim to increase climate resilience in the slope populations.


Assuntos
Antozoários/genética , Recifes de Corais , Dinoflagellida/genética , Simbiose/genética , Aclimatação , Adaptação Fisiológica/genética , Animais , Antozoários/crescimento & desenvolvimento , Antozoários/microbiologia , Dinoflagellida/crescimento & desenvolvimento , Ecossistema , Fluxo Gênico , Genética Populacional , Genoma/genética , Microbiota/genética , Fotossíntese/genética
4.
Coral Reefs ; 36(2): 447-452, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28579915

RESUMO

Mesophotic coral ecosystems (MCEs) are generally poorly studied, and our knowledge of lower MCEs (below 60 m depth) is largely limited to visual surveys. Here, we provide a first detailed assessment of the prokaryotic community associated with scleractinian corals over a depth gradient to the lower mesophotic realm (15-85 m). Specimens of three Caribbean coral species exhibiting differences in their depth distribution ranges (Agaricia grahamae, Madracis pharensis and Stephanocoenia intersepta) were collected with a manned submersible on the island of Curaçao, and their prokaryotic communities assessed using 16S rRNA gene sequencing analysis. Corals with narrower depth distribution ranges (depth-specialists) were associated with a stable prokaryotic community, whereas corals with a broader niche range (depth-generalists) revealed a higher variability in their prokaryotic community. The observed depth effects match previously described patterns in Symbiodinium depth zonation. This highlights the contribution of structured microbial communities over depth to the coral's ability to colonize a broader depth range.

5.
Zookeys ; 1203: 253-323, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855791

RESUMO

Museum collections are an important source for resolving taxonomic issues and species delimitation. Type specimens as name-bearing specimens, traditionally used in morphology-based taxonomy, are, due to the progress in historical DNA methodology, increasingly used in molecular taxonomic studies. Museum collections are subject to constant deterioration and major disasters. The digitisation of collections offers a partial solution to these problems and makes museum collections more accessible to the wider scientific community. The Extended Specimen Approach (ESA) is a method of digitisation that goes beyond the physical specimen to include the historical information stored in the collection. The collections of the Natural History Museum Vienna represent one of the largest non-university research centres in Europe and, due to their size and numerous type specimens, are frequently used for taxonomic studies by visiting and resident scientists. Recently, a version of ESA was presented in the common catalogue of the Fish and Evertebrata Varia collections and extended to include genetic information on type specimens in a case study of a torpedo ray. Here the case study was extended to a heterogeneous selection of historical type series from different collections with the type locality of Vienna. The goal was to apply the ESA, including genetic data on a selected set of type material: three parasitic worms, three myriapods, two insects, twelve fishes, and one bird species. Five hundred digital items (photographs, X-rays, scans) were produced, and genetic analysis was successful in eleven of the 21 type series. In one case a complete mitochondrial genome was assembled, and in another case ten short fragments (100-230 bp) of the cytochrome oxidase I gene were amplified and sequenced. For five type series, genetic analysis confirmed their taxonomic status as previously recognised synonyms, and for one the analysis supported its status as a distinct species. For two species, genetic information was provided for the first time. This catalogue thus demonstrates the usefulness of ESA in providing digitised data of types that can be easily made available to scientists worldwide for further study.

6.
Environ Microbiome ; 19(1): 5, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225668

RESUMO

Marine bacterioplankton underpin the health and function of coral reefs and respond in a rapid and sensitive manner to environmental changes that affect reef ecosystem stability. Numerous meta-omics surveys over recent years have documented persistent associations of opportunistic seawater microbial taxa, and their associated functions, with metrics of environmental stress and poor reef health (e.g. elevated temperature, nutrient loads and macroalgae cover). Through positive feedback mechanisms, disturbance-triggered heterotrophic activity of seawater microbes is hypothesised to drive keystone benthic organisms towards the limit of their resilience and translate into shifts in biogeochemical cycles which influence marine food webs, ultimately affecting entire reef ecosystems. However, despite nearly two decades of work in this space, a major limitation to using seawater microbes in reef monitoring is a lack of a unified and focused approach that would move beyond the indicator discovery phase and towards the development of rapid microbial indicator assays for (near) real-time reef management and decision-making. By reviewing the current state of knowledge, we provide a comprehensive framework (defined as five phases of research and innovation) to catalyse a shift from fundamental to applied research, allowing us to move from descriptive to predictive reef monitoring, and from reactive to proactive reef management.

7.
BMC Evol Biol ; 13: 205, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24059868

RESUMO

BACKGROUND: Scleractinian corals and their algal endosymbionts (genus Symbiodinium) exhibit distinct bathymetric distributions on coral reefs. Yet, few studies have assessed the evolutionary context of these ecological distributions by exploring the genetic diversity of closely related coral species and their associated Symbiodinium over large depth ranges. Here we assess the distribution and genetic diversity of five agariciid coral species (Agaricia humilis, A. agaricites, A. lamarcki, A. grahamae, and Helioseris cucullata) and their algal endosymbionts (Symbiodinium) across a large depth gradient (2-60 m) covering shallow to mesophotic depths on a Caribbean reef. RESULTS: The five agariciid species exhibited distinct depth distributions, and dominant Symbiodinium associations were found to be species-specific, with each of the agariciid species harbouring a distinct ITS2-DGGE profile (except for a shared profile between A. lamarcki and A. grahamae). Only A. lamarcki harboured different Symbiodinium types across its depth distribution (i.e. exhibited symbiont zonation). Phylogenetic analysis (atp6) of the coral hosts demonstrated a division of the Agaricia genus into two major lineages that correspond to their bathymetric distribution ("shallow": A. humilis / A. agaricites and "deep": A. lamarcki / A. grahamae), highlighting the role of depth-related factors in the diversification of these congeneric agariciid species. The divergence between "shallow" and "deep" host species was reflected in the relatedness of the associated Symbiodinium (with A. lamarcki and A. grahamae sharing an identical Symbiodinium profile, and A. humilis and A. agaricites harbouring a related ITS2 sequence in their Symbiodinium profiles), corroborating the notion that brooding corals and their Symbiodinium are engaged in coevolutionary processes. CONCLUSIONS: Our findings support the hypothesis that the depth-related environmental gradient on reefs has played an important role in the diversification of the genus Agaricia and their associated Symbiodinium, resulting in a genetic segregation between coral host-symbiont communities at shallow and mesophotic depths.


Assuntos
Antozoários/fisiologia , Dinoflagellida/classificação , Dinoflagellida/fisiologia , Animais , Antozoários/genética , Região do Caribe , Recifes de Corais , Dinoflagellida/genética , Ecossistema , Meio Ambiente , Variação Genética , Filogenia , Simbiose
8.
Microorganisms ; 10(10)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36296266

RESUMO

The fitness of the endangered green sea turtle (Chelonia mydas) may be strongly affected by its gut microbiome, as microbes play important roles in host nutrition and health. This study aimed at establishing environmental microbial baselines that can be used to assess turtle health under altered future conditions. We characterized the microbiome associated with the gastrointestinal tract of green turtles from Guinea Bissau in different life stages and associated with their food items, using 16S rRNA metabarcoding. We found that the most abundant (% relative abundance) bacterial phyla across the gastrointestinal sections were Proteobacteria (68.1 ± 13.9% "amplicon sequence variants", ASVs), Bacteroidetes (15.1 ± 10.1%) and Firmicutes (14.7 ± 21.7%). Additionally, we found the presence of two red algae bacterial indicator ASVs (the Alphaproteobacteria Brucella pinnipedialis with 75 ± 0% and a Gammaproteobacteria identified as methanotrophic endosymbiont of Bathymodiolus, with <1%) in cloacal compartments, along with six bacterial ASVs shared only between cloacal and local environmental red algae samples. We corroborate previous results demonstrating that green turtles fed on red algae (but, to a lower extent, also seagrass and brown algae), thus, acquiring microbial components that potentially aid them digest these food items. This study is a foundation for better understanding the microbial composition of sea turtle digestive tracts.

9.
Curr Biol ; 32(12): 2596-2609.e7, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35561678

RESUMO

Reef-building corals are endangered animals with a complex colonial organization. Physiological mechanisms connecting multiple polyps and integrating them into a coral colony are still enigmatic. Using live imaging, particle tracking, and mathematical modeling, we reveal how corals connect individual polyps and form integrated polyp groups via species-specific, complex, and stable networks of currents at their surface. These currents involve surface mucus of different concentrations, which regulate joint feeding of the colony. Inside the coral, within the gastrovascular system, we expose the complexity of bidirectional branching streams that connect individual polyps. This system of canals extends the surface area by 4-fold and might improve communication, nutrient supply, and symbiont transfer. Thus, individual polyps integrate via complex liquid dynamics on the surface and inside the colony.


Assuntos
Antozoários , Animais , Antozoários/fisiologia , Recifes de Corais , Meio Ambiente , Especificidade da Espécie
10.
Life (Basel) ; 11(11)2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34833075

RESUMO

Macroalgae play an intricate role in microbial-mediated coral reef degradation processes due to the release of dissolved nutrients. However, temporal variabilities of macroalgal surface biofilms and their implication on the wider reef system remain poorly characterized. Here, we study the microbial biofilm of the dominant reef macroalgae Sargassum over a period of one year at an inshore Great Barrier Reef site (Magnetic Island, Australia). Monthly sampling of the Sargassum biofilm links the temporal taxonomic and putative functional metabolic microbiome changes, examined using 16S rRNA gene amplicon and metagenomic sequencing, to the pronounced growth-reproduction-senescence cycle of the host. Overall, the macroalgal biofilm was dominated by the heterotrophic phyla Firmicutes (35% ± 5.9% SD) and Bacteroidetes (12% ± 0.6% SD); their relative abundance ratio shifted significantly along the annual growth-reproduction-senescence cycle of Sargassum. For example, Firmicutes were 1.7 to 3.9 times more abundant during host growth and reproduction cycles than Bacteroidetes. Both phyla varied in their carbohydrate degradation capabilities; hence, temporal fluctuations in the carbohydrate availability are potentially linked to the observed shift. Dominant heterotrophic macroalgal biofilm members, such as Firmicutes and Bacteroidetes, are implicated in exacerbating or ameliorating the release of dissolved nutrients into the ambient environment, though their contribution to microbial-mediated reef degradation processes remains to be determined.

11.
Transcult Psychiatry ; 57(3): 445-454, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32216543

RESUMO

Caregiving and bereavement outcomes are strongly influenced by socio-cultural context. Past research has found higher levels of caregiver burden and psychological morbidity in Portuguese compared to Brazilian caregivers. This study compared Brazilian and Portuguese family caregivers in palliative care to identify differences in psychological morbidity and caregiver burden and their relationship with psychosocial factors such as sociodemographic variables, circumstances of end-of-life care and dying, social support, family functioning, and perception of quality of care. Prospective data were collected from convenience samples of family caregivers in Brazil (T0 n = 60; T1 n = 35) and Portugal (T0 n = 75; T1 n = 29) at two separate time points-during caregiving (T0), and during the first two months of bereavement (T1). The study samples consisted mostly of women, offspring, and spouses. In both countries, family caregivers devoted most of their day to taking care of their sick relatives and reported a lack of practical support. Portuguese caregivers had higher levels of burden than Brazilian caregivers, and in both populations a greater burden was associated with more psychopathological symptoms. Higher caregiver burden among Portuguese caregivers was associated with the circumstances of death and the perceived lack of emotional support. Among Portuguese caregivers, symptomatology persisted during bereavement, reaching significantly higher levels of anxiety, somatization, and peritraumatic symptoms compared to the Brazilian sample. These results show differences between family caregiver samples in Portugal and Brazil during the bereavement process. Understanding the underlying cultural patterns and mechanisms requires future research.


Assuntos
Luto , Cuidadores/psicologia , Família/psicologia , Pesar , Cuidados Paliativos , Idoso , Idoso de 80 Anos ou mais , Brasil , Comparação Transcultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Estudos Prospectivos , Qualidade de Vida , Apoio Social , Fatores Socioeconômicos
12.
PeerJ ; 8: e9644, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874778

RESUMO

Corals are associated with diverse microbial assemblages; however, the spatial-temporal dynamics of intra-species microbial interactions are poorly understood. The coral-associated microbial community varies substantially between tissue and mucus microhabitats; however, the factors controlling the occurrence, abundance, and distribution of microbial taxa over time have rarely been explored for different coral compartments simultaneously. Here, we test (1) differentiation in microbiome diversity and composition between coral compartments (surface mucus and tissue) of two Acropora hosts (A. tenuis and A. millepora) common along inshore reefs of the Great Barrier Reef, as well as (2) the potential linkage between shifts in individual coral microbiome families and underlying host and environmental parameters. Amplicon based 16S ribosomal RNA gene sequencing of 136 samples collected over 14 months, revealed significant differences in bacterial richness, diversity and community structure among mucus, tissue and the surrounding seawater. Seawater samples were dominated by members of the Synechococcaceae and Pelagibacteraceae bacterial families. The mucus microbiome of Acropora spp. was dominated by members of Flavobacteriaceae, Synechococcaceae and Rhodobacteraceae and the tissue was dominated by Endozoicimonaceae. Mucus microbiome in both Acropora species was primarily correlated with seawater parameters including levels of chlorophyll a, ammonium, particulate organic carbon and the sum of nitrate and nitrite. In contrast, the correlation of the tissue microbiome to the measured environmental (i.e., seawater parameters) and host health physiological factors differed between host species, suggesting host-specific modulation of the tissue-associated microbiome to intrinsic and extrinsic factors. Furthermore, the correlation between individual coral microbiome members and environmental factors provides novel insights into coral microbiome-by-environment dynamics and hence has potential implications for current reef restoration and management efforts (e.g. microbial monitoring and observatory programs).

13.
ISME J ; 14(6): 1435-1450, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32123297

RESUMO

Microbially mediated processes contribute to coral reef resilience yet, despite extensive characterisation of microbial community variation following environmental perturbation, the effect on microbiome function is poorly understood. We undertook metagenomic sequencing of sponge, macroalgae and seawater microbiomes from a macroalgae-dominated inshore coral reef to define their functional potential and evaluate seasonal shifts in microbially mediated processes. In total, 125 high-quality metagenome-assembled genomes were reconstructed, spanning 15 bacterial and 3 archaeal phyla. Multivariate analysis of the genomes relative abundance revealed changes in the functional potential of reef microbiomes in relation to seasonal environmental fluctuations (e.g. macroalgae biomass, temperature). For example, a shift from Alphaproteobacteria to Bacteroidota-dominated seawater microbiomes occurred during summer, resulting in an increased genomic potential to degrade macroalgal-derived polysaccharides. An 85% reduction of Chloroflexota was observed in the sponge microbiome during summer, with potential consequences for nutrition, waste product removal, and detoxification in the sponge holobiont. A shift in the Firmicutes:Bacteroidota ratio was detected on macroalgae over summer with potential implications for polysaccharide degradation in macroalgal microbiomes. These results highlight that seasonal shifts in the dominant microbial taxa alter the functional repertoire of host-associated and seawater microbiomes, and highlight how environmental perturbation can affect microbially mediated processes in coral reef ecosystems.


Assuntos
Bactérias/genética , Microbiota , Poríferos/microbiologia , Alga Marinha/genética , Animais , Archaea/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Biomassa , Recifes de Corais , Metagenoma , Estações do Ano , Água do Mar/microbiologia , Alga Marinha/classificação
14.
Commun Biol ; 3(1): 442, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796904

RESUMO

Microorganisms are fundamental drivers of biogeochemical cycling, though their contribution to coral reef ecosystem functioning is poorly understood. Here, we infer predictors of bacterioplankton community dynamics across surface-waters of the Great Barrier Reef (GBR) through a meta-analysis, combining microbial with environmental data from the eReefs platform. Nutrient dynamics and temperature explained 41.4% of inter-seasonal and cross-shelf variation in bacterial assemblages. Bacterial families OCS155, Cryomorphaceae, Flavobacteriaceae, Synechococcaceae and Rhodobacteraceae dominated inshore reefs and their relative abundances positively correlated with nutrient loads. In contrast, Prochlorococcaceae negatively correlated with nutrients and became increasingly dominant towards outershelf reefs. Cyanobacteria in Prochlorococcaceae and Synechococcaceae families occupy complementary cross-shelf biogeochemical niches; their abundance ratios representing a potential indicator of GBR nutrient levels. One Flavobacteriaceae-affiliated taxa was putatively identified as diagnostic for ecosystem degradation. Establishing microbial observatories along GBR environmental gradients will facilitate robust assessments of microbial contributions to reef health and inform tipping-points in reef condition.


Assuntos
Antozoários/microbiologia , Recifes de Corais , Microbiota , Microbiologia da Água , Animais , Bactérias/crescimento & desenvolvimento , Bases de Dados como Assunto
15.
ISME J ; 14(9): 2211-2222, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32444811

RESUMO

Microbiome assemblages of plants and animals often show a degree of correlation with host phylogeny; an eco-evolutionary pattern known as phylosymbiosis. Using 16S rRNA gene sequencing to profile the microbiome, paired with COI, 18S rRNA and ITS1 host phylogenies, phylosymbiosis was investigated in four groups of coral reef invertebrates (scleractinian corals, octocorals, sponges and ascidians). We tested three commonly used metrics to evaluate the extent of phylosymbiosis: (a) intraspecific versus interspecific microbiome variation, (b) topological comparisons between host phylogeny and hierarchical clustering (dendrogram) of host-associated microbial communities, and (c) correlation of host phylogenetic distance with microbial community dissimilarity. In all instances, intraspecific variation in microbiome composition was significantly lower than interspecific variation. Similarly, topological congruency between host phylogeny and the associated microbial dendrogram was more significant than would be expected by chance across all groups, except when using unweighted UniFrac distance (compared with weighted UniFrac and Bray-Curtis dissimilarity). Interestingly, all but the ascidians showed a significant positive correlation between host phylogenetic distance and associated microbial dissimilarity. Our findings provide new perspectives on the diverse nature of marine phylosymbioses and the complex roles of the microbiome in the evolution of marine invertebrates.


Assuntos
Recifes de Corais , Simbiose , Animais , Invertebrados , Filogenia , RNA Ribossômico 16S/genética
16.
Microbiome ; 7(1): 94, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227022

RESUMO

BACKGROUND: Coral reefs are facing unprecedented pressure on local and global scales. Sensitive and rapid markers for ecosystem stress are urgently needed to underpin effective management and restoration strategies. Although the fundamental contribution of microbes to the stability and functioning of coral reefs is widely recognised, it remains unclear how different reef microbiomes respond to environmental perturbations and whether microbiomes are sensitive enough to predict environmental anomalies that can lead to ecosystem stress. However, the lack of coral reef microbial baselines hinders our ability to study the link between shifts in microbiomes and ecosystem stress. In this study, we established a comprehensive microbial reference database for selected Great Barrier Reef sites to assess the diagnostic value of multiple free-living and host-associated reef microbiomes to infer the environmental state of coral reef ecosystems. RESULTS: A comprehensive microbial reference database, originating from multiple coral reef microbiomes (i.e. seawater, sediment, corals, sponges and macroalgae), was generated by 16S rRNA gene sequencing for 381 samples collected over the course of 16 months. By coupling this database to environmental parameters, we showed that the seawater microbiome has the greatest diagnostic value to infer shifts in the surrounding reef environment. In fact, 56% of the observed compositional variation in the microbiome was explained by environmental parameters, and temporal successions in the seawater microbiome were characterised by uniform community assembly patterns. Host-associated microbiomes, in contrast, were five-times less responsive to the environment and their community assembly patterns were generally less uniform. By applying a suite of indicator value and machine learning approaches, we further showed that seawater microbial community data provide an accurate prediction of temperature and eutrophication state (i.e. chlorophyll concentration and turbidity). CONCLUSION: Our results reveal that free-living microbial communities have a high potential to infer environmental parameters due to their environmental sensitivity and predictability. This highlights the diagnostic value of microorganisms and illustrates how long-term coral reef monitoring initiatives could be enhanced by incorporating assessments of microbial communities in seawater. We therefore recommend timely integration of microbial sampling into current coral reef monitoring initiatives.


Assuntos
Antozoários/microbiologia , Recifes de Corais , Monitoramento Ambiental , Microbiota , Água do Mar/microbiologia , Animais , Austrália , Bactérias/classificação , Biodiversidade , RNA Ribossômico 16S
17.
Nat Commun ; 9(1): 3447, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30181537

RESUMO

Our rapidly warming climate is threatening coral reefs as thermal anomalies trigger mass coral bleaching events. Deep (or "mesophotic") coral reefs are hypothesised to act as major ecological refuges from mass bleaching, but empirical assessments are limited. We evaluated the potential of mesophotic reefs within the Great Barrier Reef (GBR) and adjacent Coral Sea to act as thermal refuges by characterising long-term temperature conditions and assessing impacts during the 2016 mass bleaching event. We found that summer upwelling initially provided thermal relief at upper mesophotic depths (40 m), but then subsided resulting in anomalously warm temperatures even at depth. Bleaching impacts on the deep reefs were severe (40% bleached and 6% dead colonies at 40 m) but significantly lower than at shallower depths (60-69% bleached and 8-12% dead at 5-25 m). While we confirm that deep reefs can offer refuge from thermal stress, we highlight important caveats in terms of the transient nature of the protection and their limited ability to provide broad ecological refuge.


Assuntos
Antozoários/fisiologia , Recifes de Corais , Animais , Austrália , Ecossistema , Monitoramento Ambiental/métodos , Estações do Ano , Água do Mar , Temperatura
18.
Zootaxa ; 4471(3): 473-492, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30313392

RESUMO

The colonial stony coral genus Madracis is cosmopolitan, lives in shallow and deep water habitats, and includes zooxanthellate, azooxanthellate and facultative symbiotic species. One of its species, Madracis pharensis, has been recorded from the Mediterranean and East Atlantic, where it forms small knobby and facultative zooxanthellate colonies (also named M. pharensis f. pharensis), and from the tropical Caribbean, where it also occurs in a massive and zooxanthellate form (named M. pharensis f. luciphila by some). These two forms have been previously found to host different Symbiodinium species. In this study, species boundaries and phylogenetic relationships between these two Madracis pharensis forms (from the Mediterranean Sea and the Caribbean), M. senaria, and the Indo-west Pacific M. kirbyi were analyzed through an integrated systematics approach, including corallite dimensions, micromorphology and two molecular markers (ITS and ATP8). Significant genetic and morphological differences were found between all the examined Madracis species, and between M. pharensis from the Mediterranean Sea and M. pharensis f. luciphila from the Caribbean in particular. Based on these results, the latter does not represent a zooxanthellate ecomorph of the former but a different species. Its identity remains to be ascertained and its relationship with the Caribbean M. decactis, with which it bears morphologic resemblance, must be investigated in further studies. Overall, the presence of cryptic Madracis species in the Easter and Central Atlantic Ocean remains to be evaluated.


Assuntos
Antozoários , Filogenia , Animais , Oceano Atlântico , Região do Caribe , Mar Mediterrâneo
19.
Biosci. j. (Online) ; 38: e38028, Jan.-Dec. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1395417

RESUMO

Whiteflies (Hemiptera: Aleyrodidae) are a diverse group of sap-sucking insect species that can cause severe damage in crops with global economic importance. Hops (Humulus lupulus L.) are a crop with considerable value for the brewing and pharmaceutical industries worldwide. The aim of the current study is to register whitefly species associated with this plant in Brazil. Specimens were collected from H. lupulus leaves in four different counties in Rio de Janeiro state (Cachoeiras de Macacu, Cordeiro, Nova Friburgo and Seropédica). Whiteflies belonging to nine genera and distributed in two subfamilies (Aleurodicinae and Aleyrodinae) were identified. Nine hop varieties (i.e., Brazylinsk, Cascade, Chinook, Columbus, Hallertau, Nugget, Saaz, Spalt, and Victoria) are used as host plants by these insects in Brazil. Except for Trialeurodes vaporariorum (Westwood), the other identified species were recorded in hop crops for the first time.


Assuntos
Humulus , Interações Hospedeiro-Patógeno , Hemípteros , Interações Hospedeiro-Parasita
20.
ISME J ; 10(9): 2280-92, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26953605

RESUMO

Microbes are well-recognized members of the coral holobiont. However, little is known about the short-term dynamics of mucus-associated microbial communities under natural conditions and after disturbances, and how these dynamics relate to the host's health. Here we examined the natural variability of prokaryotic communities (based on 16S ribosomal RNA gene amplicon sequencing) associating with the surface mucus layer (SML) of Porites astreoides, a species exhibiting cyclical mucus aging and shedding. Shifts in the prokaryotic community composition during mucus aging led to the prevalence of opportunistic and potentially pathogenic bacteria (Verrucomicrobiaceae and Vibrionaceae) in aged mucus and to a twofold increase in prokaryotic abundance. After the release of aged mucus sheets, the community reverted to its original state, dominated by Endozoicimonaceae and Oxalobacteraceae. Furthermore, we followed the fate of the coral holobiont upon depletion of its natural mucus microbiome through antibiotics treatment. After re-introduction to the reef, healthy-looking microbe-depleted corals started exhibiting clear signs of bleaching and necrosis. Recovery versus mortality of the P. astreoides holobiont was related to the degree of change in abundance distribution of the mucus microbiome. We conclude that the natural prokaryotic community inhabiting the coral SML contributes to coral health and that cyclical mucus shedding has a key role in coral microbiome dynamics.


Assuntos
Antozoários/microbiologia , Bactérias/isolamento & purificação , Biodiversidade , Microbiota , Animais , Antozoários/fisiologia , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Recifes de Corais , DNA Ribossômico/química , DNA Ribossômico/genética , Análise de Sequência de DNA
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