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1.
Mar Pollut Bull ; 149: 110560, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31542599

RESUMO

Disposal of mine tailings in marine shallow water ecosystems represents an environmental challenge, and the present paper reports results from a field study in Frænfjorden, Norway, which is subject to such disposal. Structural and functional responses of benthic infauna and epifauna were investigated along a gradient from heavy tailings deposition to reference conditions. The tailings clearly impacted the faunal composition, with lowered species number close to the outfall. Total abundance of infauna increased in the most impacted area due to dominance of opportunistic species, whereas the epifauna was reduced and represented by a few scattered specimens only. In the most impacted area functional responses included an increase in mobile carnivores/omnivores and species utilizing symbionts. Sessile and tube-living taxa, and deposit and suspension feeders decreased, probably due to smothering in combination with tailings-associated changes of the substrate. Functional diversity decreased for both infauna and epifauna, but less than the structural diversity.


Assuntos
Organismos Aquáticos/fisiologia , Ecossistema , Resíduos Industriais , Mineração , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Monitoramento Ambiental , Estuários , Sedimentos Geológicos/química , Noruega
2.
Mar Drugs ; 17(8)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370264

RESUMO

The following study reports on the first thraustochytrid isolates identified from Iceland. They were collected from three different locations off the northern coast of the country (Location A, Skagaströnd; Location B, Hveravík; and Location C, Eyjafjörður). Using 18S rDNA sequence analysis, isolates from Locations A and B were identified within the Thraustochytrium kinnei species while other isolates within the Sicyoidochytrium minutum species when compared to other known strains. Cells isolated from Locations A ( 2 . 10 ± 0 . 70 g/L) and B ( 1 . 54 ± 0 . 17 g/L) produced more biomass than the ones isolated from Location C ( 0 . 43 ± 0 . 02 g/L). This study offers the first-time examination of the utility of byproducts from fisheries as a nitrogen source in media formulation for thraustochytrids. Experiments showed that isolates produced more biomass (per unit of substrate) when cultured on nitrogen of marine ( 2 . 55 ± 0 . 74 g/L) as compared to of commercial origin (  1 . 06 ± 0 . 57 g/L). Glycerol ( 2 . 43 ± 0 . 56 g/L) was a better carbon source than glucose ( 1 . 84 ± 0 . 57 g/L) in growth studies. Fatty acid (FA) profiles showed that the isolates from Location C (S. minutum) had low ratios of monounsaturated ( 4 . 21 ± 2 . 96 % ) and omega-6 ( 0 . 68 ± 0 . 59 % ) FAs. However, the isolates also had high ratios of docosahexaenoic acid (DHA; 35 . 65 ± 1 . 73 % ) and total omega-3 FAs ( 40 . 39 ± 2 . 39 % ), indicating that they could serve as a source of marine oils for human consumption and in aquaculture feeds. The T. kinnei isolates from Location A could be used in biodiesel production due to their high ratios of monounsaturated ( 18 . 38 ± 6 . 27 % ) long chain ( 57 . 43 ± 8 . 27 % ) FAs.


Assuntos
Organismos Aquáticos/metabolismo , Biocombustíveis , Microbiologia Industrial/métodos , Estramenópilas/metabolismo , Organismos Aquáticos/isolamento & purificação , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Ácidos Graxos Ômega-3/isolamento & purificação , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/isolamento & purificação , Ácidos Graxos Ômega-6/metabolismo , Pesqueiros , Glicerol/química , Islândia , Nitrogênio/química , Estramenópilas/isolamento & purificação
3.
Biotechnol Lett ; 41(10): 1187-1200, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418101

RESUMO

OBJECTIVES: Bifunctional alginate lyase can efficiently saccharify alginate biomass and prepare functional oligosaccharides of alginate. RESULTS: A new BP-2 strain that produces alginate lyase was screened and identified from rotted Sargassum. A new alginate lyase, Alg17B, belonging to the polysaccharide lyase family 17, was isolated and purified from BP-2 fermentation broth by freeze-drying, dialysis, and ion exchange chromatography. The enzymatic properties of the purified lyase were investigated. The molecular weight of Alg17B was approximately 77 kDa, its optimum reaction temperature was 40-45 °C, and its optimum reaction pH was 7.5-8.0. The enzyme was relatively stable at pH 7.0-8.0, with a temperature range of 25-35 °C, and the specific activity of the purified enzyme reached 4036 U/mg. A low Na+ concentration stimulated Alg17B enzyme activity, but Ca2+, Zn2+, and other metal ions inhibited it. Substrate specificity analysis, thin-layer chromatography, and mass spectrometry showed that Alg17B is an alginate lyase that catalyses the hydrolysis of sodium alginate, polymannuronic acid (polyM) and polyguluronic acid to produce monosaccharides and low molecular weight oligosaccharides. Alg17B is also bifunctional, exhibiting both endolytic and exolytic activities toward alginate, and has a wide substrate utilization range with a preference for polyM. CONCLUSIONS: Alg17B can be used to saccharify the main carbohydrate, alginate, in the ethanolic production of brown algae fuel as well as in preparing and researching oligosaccharides.


Assuntos
Organismos Aquáticos/enzimologia , Gammaproteobacteria/enzimologia , Polissacarídeo-Liase/isolamento & purificação , Polissacarídeo-Liase/metabolismo , Sargassum/microbiologia , Alginatos/metabolismo , Ácido Algínico/metabolismo , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Ativadores de Enzimas/análise , Inibidores Enzimáticos/análise , Estabilidade Enzimática , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Concentração de Íons de Hidrogênio , Hidrólise , Peso Molecular , Monossacarídeos/metabolismo , Oligossacarídeos/metabolismo , Polissacarídeo-Liase/química , Polissacarídeo-Liase/genética , Polissacarídeos Bacterianos/metabolismo , Especificidade por Substrato , Temperatura Ambiente
4.
Sensors (Basel) ; 19(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344849

RESUMO

In recent advanced information society, it is important to individually identify products or living organisms automatically and quickly. However, with the current identifying technology such as RFID tag or biometrics, it is difficult to apply to amphibians such as frogs or newts because of its size, stability, weakness under a wet environment and so on. Thus, this research aims to establish a system that can trace small amphibians easily even in a wet environment and keep stable sensing for a long time. The magnetism was employed for identification because it was less influenced by water for a long time. Here, a novel magnetization-free micro-magnetic tag is proposed and fabricated with low cost for installation to a living target sensed by Magneto-Optical sensor for high throughput sensing. The sensing ability of the proposed method, which was evaluated by image analysis, indicated that it was less than half of the target value (1 mm) both in the water and air. The FEM analysis showed that it is approximately twice the actual identification ability under ideal conditions, which suggests that the actual sensing ability can be extended by further improvement of the sensing system. The developed magnetization-free micro-magnetic tag can contribute to keep up the increasing demand to identify a number of samples under a wet environment especially with the development of gene technology.


Assuntos
Organismos Aquáticos/isolamento & purificação , Técnicas Biossensoriais , Dispositivos Ópticos , Organismos Aquáticos/química , Imãs , Dispositivo de Identificação por Radiofrequência , Água/química
5.
Mar Pollut Bull ; 1452019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31256853

RESUMO

In the early 1990s, a cliff-face disposal-system discharging approximately 940 ML/day, or 80% of sewage generated by the City of Sydney (Australia) (population 3.3 million) was replaced by three deepwater ocean outfalls. An 18-year benthic infauna monitoring study was undertaken to address earlier concerns of long-term accumulation from sewage discharges and potential adverse effects on the marine environment. Assessment of outfall community structure indicated organic input from discharges has not resulted in sediment anoxia. The current post-commissioning investigation detected a gradual change in community structure from north to south in the study area, which was also displayed in taxonomic turnover south of the Malabar outfall. Temporal fluctuation in community structure detected at the three outfall and three reference locations in the current study was also noted in the pre-commissioning study at these locations. Evidence provided by this study indicated the Sydney deepwater ocean outfalls do not cause significant ecological impact.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/efeitos dos fármacos , Água do Mar/química , Esgotos/análise , Poluentes da Água/farmacologia , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Austrália , Cidades , Ecossistema , Monitoramento Ambiental , Oceanos e Mares , Poluentes da Água/análise
6.
Mar Drugs ; 17(4)2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30978942

RESUMO

The emergence of antibiotic resistance and viruses with high epidemic potential made unexplored marine environments an appealing target source for new metabolites. Marine fungi represent one of the most suitable sources for the discovery of new compounds. Thus, the aim of this work was (i) to isolate and identify fungi associated with the Atlantic sponge Grantia compressa; (ii) to study the fungal metabolites by applying the OSMAC approach (one strain; many compounds); (iii) to test fungal compounds for their antimicrobial activities. Twenty-one fungal strains (17 taxa) were isolated from G. compressa. The OSMAC approach revealed an astonishing metabolic diversity in the marine fungus Eurotium chevalieri MUT 2316, from which 10 compounds were extracted, isolated, and characterized. All metabolites were tested against viruses and bacteria (reference and multidrug-resistant strains). Dihydroauroglaucin completely inhibited the replication of influenza A virus; as for herpes simplex virus 1, total inhibition of replication was observed for both physcion and neoechinulin D. Six out of 10 compounds were active against Gram-positive bacteria with isodihydroauroglaucin being the most promising compound (minimal inhibitory concentration (MIC) 4-64 µg/mL) with bactericidal activity. Overall, G. compressa proved to be an outstanding source of fungal diversity. Marine fungi were capable of producing different metabolites; in particular, the compounds isolated from E. chevalieri showed promising bioactivity against well-known and emerging pathogens.


Assuntos
Antibacterianos/farmacologia , Antivirais/farmacologia , Biotecnologia/métodos , Eurotium/metabolismo , Poríferos/microbiologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Organismos Aquáticos/metabolismo , Biodiversidade , Cães , Eurotium/genética , Eurotium/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Vírus da Influenza A/efeitos dos fármacos , Células Madin Darby de Rim Canino , Testes de Sensibilidade Microbiana , Células Vero , Replicação Viral/efeitos dos fármacos
7.
Nat Commun ; 10(1): 1644, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30967538

RESUMO

Much recent marine microbial research has focused on sponges, but very little is known about how the sponge microbiome fits in the greater coral reef microbial metacommunity. Here, we present an extensive survey of the prokaryote communities of a wide range of biotopes from Indo-Pacific coral reef environments. We find a large variation in operational taxonomic unit (OTU) richness, with algae, chitons, stony corals and sea cucumbers housing the most diverse prokaryote communities. These biotopes share a higher percentage and number of OTUs with sediment and are particularly enriched in members of the phylum Planctomycetes. Despite having lower OTU richness, sponges share the greatest percentage (>90%) of OTUs with >100 sequences with the environment (sediment and/or seawater) although there is considerable variation among sponge species. Our results, furthermore, highlight that prokaryote microorganisms are shared among multiple coral reef biotopes, and that, although compositionally distinct, the sponge prokaryote community does not appear to be as sponge-specific as previously thought.


Assuntos
Organismos Aquáticos/isolamento & purificação , Bactérias/isolamento & purificação , Recifes de Corais , Microbiota , Poríferos/microbiologia , Animais , Organismos Aquáticos/genética , Bactérias/genética , DNA Bacteriano/isolamento & purificação , Sedimentos Geológicos/microbiologia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Taiwan , Tailândia
8.
J Microbiol ; 57(4): 252-262, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30929228

RESUMO

Phytoplankton and bacterioplankton play a key role in carbon cycling of aquatic ecosystems. In this study, we found that co-occurrence patterns between different types of phytoplankton, bacterioplankton, and environmental parameters in Lake Baikal during spring were different over the course of three consecutive years. The composition of phytoplankton and bacterial communities was investigated using microscopy and 16S rRNA gene pyrosequencing, respectively. Non-metric multidimensional scaling (NMDS) revealed a relationship between the structure of phytoplankton and bacterial communities and temperature, location, and sampling year. Associations of bacteria with diatoms, green microalgae, chrysophyte, and cryptophyte were identified using microscopy. Cluster analysis revealed similar correlation patterns between phytoplankton abundance, number of attached bacteria, ratio of bacteria per phytoplankton cell and environmental parameters. Positive and negative correlations between different species of phytoplankton, heterotrophic bacteria and environmental parameters may indicate mutualistic or competitive relationships between microorganisms and their preferences to the environment.


Assuntos
Organismos Aquáticos/isolamento & purificação , Bactérias/isolamento & purificação , Lagos/microbiologia , Lagos/parasitologia , Fitoplâncton/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Bactérias/classificação , Bactérias/genética , Ecossistema , Lagos/química , Filogenia , Fitoplâncton/classificação , Fitoplâncton/genética , Estações do Ano , Temperatura Ambiente
9.
Mar Pollut Bull ; 141: 332-342, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955741

RESUMO

The present study aimed to develop monitoring methods for shallow water sessile and mobile epifauna with the main focus on enhancing the chance of early detection for new non-indigenous species (NIS) invasions. The field sampling was conducted between June and September in 2012, in the Archipelago Sea (Finland). The tested monitoring methods included baited traps that capture organisms and habitat collectors that provide habitat and refuges for organisms, as well as fouling plates. Catch efficiency of a trap/collector was defined as the number of NIS and all species caught, including their abundances. The American collector with oyster shells (habitat collector) caught the highest number of NIS, and their use is recommended in all places, where oyster shells are easily accessible. Sampling of all habitats of interest between 1 and 2 m depth is recommended with at least three habitat collectors per site.


Assuntos
Organismos Aquáticos/isolamento & purificação , Ecossistema , Monitoramento Ambiental/métodos , Espécies Introduzidas , Animais , Finlândia , Oceanos e Mares
10.
mBio ; 10(2)2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837337

RESUMO

Terrestrial fungi play critical roles in nutrient cycling and food webs and can shape macroorganism communities as parasites and mutualists. Although estimates for the number of fungal species on the planet range from 1.5 to over 5 million, likely fewer than 10% of fungi have been identified so far. To date, a relatively small percentage of described species are associated with marine environments, with ∼1,100 species retrieved exclusively from the marine environment. Nevertheless, fungi have been found in nearly every marine habitat explored, from the surface of the ocean to kilometers below ocean sediments. Fungi are hypothesized to contribute to phytoplankton population cycles and the biological carbon pump and are active in the chemistry of marine sediments. Many fungi have been identified as commensals or pathogens of marine animals (e.g., corals and sponges), plants, and algae. Despite their varied roles, remarkably little is known about the diversity of this major branch of eukaryotic life in marine ecosystems or their ecological functions. This perspective emerges from a Marine Fungi Workshop held in May 2018 at the Marine Biological Laboratory in Woods Hole, MA. We present the state of knowledge as well as the multitude of open questions regarding the diversity and function of fungi in the marine biosphere and geochemical cycles.


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Biodiversidade , Fungos/classificação , Fungos/isolamento & purificação , Sedimentos Geológicos/microbiologia , Água do Mar/microbiologia
11.
Bioprocess Biosyst Eng ; 42(4): 603-610, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30617415

RESUMO

Polyhydroxybutyrates (PHB) are biodegradable polymers that are produced by various microbes, including Ralstonia, Pseudomonas, and Bacillus species. In this study, a Vibrio proteolyticus strain, which produces a high level of polyhydroxyalkanoate (PHA), was isolated from the Korean marine environment. To determine optimal growth and production conditions, environments with different salinity, carbon sources, and nitrogen sources were evaluated. We found that the use of a medium containing 2% (w/v) fructose, 0.3% (w/v) yeast extract, and 5% (w/v) sodium chloride (NaCl) in M9 minimal medium resulted in high PHA content (54.7%) and biomass (4.94 g/L) over 48 h. Addition of propionate resulted in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) copolymer as propionate acts as a precursor for the HV unit. In these conditions, the bacteria produced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) containing a 15.8% 3HV fraction with 0.3% propionate added as the substrate. To examine the possibility of using unsterilized media with high NaCl content for PHB production, V. proteolyticus was cultured in sterilized and unsterilized conditions. Our results indicated a higher growth, leading to a dominant population in unsterilized conditions and higher PHB production. This study showed the conditions for halophilic PHA producers to be later implemented at a larger scale.


Assuntos
Organismos Aquáticos , Poli-Hidroxialcanoatos/biossíntese , Água do Mar/microbiologia , Vibrio , Microbiologia da Água , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Coreia (Geográfico) , Vibrio/genética , Vibrio/isolamento & purificação
12.
Bioprocess Biosyst Eng ; 42(3): 475-483, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30523447

RESUMO

Acetoin is one of the bio-based platform chemicals and its optically pure isomers are important potential intermediates and precursors in the synthesis of novel optically active materials. (3R)-acetoin could be synthesized via enzymatic catalysis, whole-cell catalysis and fermentation. In this study a marine strain of Bacillus subtilis was isolated to produce optically pure (3R)-acetoin with glucose as carbon source. The effects of nutrients on the formation of (3R)-acetoin and conversion of glucose to (3R)-acetoin were evaluated by Plackett-Burman design, and the fermentation medium was optimized by central composite design. The impact of oxygen supply on the production of (3R)-acetoin was studied at different aeration rates. Under the optimal conditions, 83.7 g/L (3R)-acetoin with an optical purity of 99.4% was achieved by fed-batch fermentation, and the conversion of glucose to (3R)-acetoin was 91.5% of the theoretical value. The results indicate the industrial potential of this strain for (3R)-acetoin production via fermentation.


Assuntos
Acetoína/metabolismo , Organismos Aquáticos/crescimento & desenvolvimento , Bacillus subtilis/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Bacillus subtilis/isolamento & purificação , Técnicas de Cultura Celular por Lotes
13.
J Antibiot (Tokyo) ; 72(1): 45-49, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30258222

RESUMO

Aranciamycin K (1) and isotirandamycin B (2) were isolated from a marine-derived Streptomyces sp. SCSIO 41399, along with the previously reported four anthracycline derivatives (3-6), and two known tirandamycin derivatives (7 and 8). Their structures including absolute configurations were determined by extensive analysis of their spectroscopic analysis and ECD calculation method. Most of the isolated compounds were tested for their cytotoxic, antibacterial, and antifungal activities. Compounds 2, 7 and 8 displayed potent bacteriostatic effects against Streptococcus agalactiae with MIC values of 11.5, 5.9 and 5.7 µM, respectively. Besides, compounds 3, 5 and 6 exhibited moderate in vitro cytotoxic activities against the K562 cell lines with IC50 values of 22.0 ± 0.20, 1.80 ± 0.01 and 12.1 ± 0.07 µM, respectively.


Assuntos
Aminoglicosídeos/farmacologia , Antraciclinas/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Organismos Aquáticos/química , Streptomyces/química , Aminoglicosídeos/química , Aminoglicosídeos/isolamento & purificação , Antraciclinas/química , Antraciclinas/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Organismos Aquáticos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Células K562/efeitos dos fármacos , Células K562/fisiologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Análise Espectral , Streptococcus agalactiae/efeitos dos fármacos , Streptomyces/isolamento & purificação
14.
J Antibiot (Tokyo) ; 72(1): 34-44, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30258223

RESUMO

4,4'-bond secalonic acid D (4,4'-SAD) is a known compound isolated from the marine-derived fungus Penicillium oxalicum. No study about the antitumor effect of this compound has been reported, except for a few focusing on its bactericidal properties. Herein, we performed an in vitro biology test and found that 4,4'-SAD stimulated the apoptosis of tumor cells in the human hepatocellular carcinoma cell lines PLC/PRF/5 and HuH-7 by activating caspase-3, caspase-8, caspase-9, PARP, p53, and cyclin B1, as well as by regulating the Bax/Bcl-2 ratio. In vivo studies showed that 4,4'-SAD had antitumor efficacy in H22 cell xenograft model. Immunohistochemical analysis revealed that 4,4'-SAD could regulate Bax expression, which is a biomarker of tumor growth. In summary, 4,4'-SAD significantly inhibited tumor growth both in vivo and in vitro.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Organismos Aquáticos/química , Hepatócitos/efeitos dos fármacos , Penicillium/química , Xantonas/isolamento & purificação , Xantonas/farmacologia , Apoptose , Organismos Aquáticos/isolamento & purificação , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Hepatócitos/fisiologia , Humanos , Imuno-Histoquímica , Penicillium/isolamento & purificação , Proteína X Associada a bcl-2/análise
15.
Drug Dev Res ; 80(1): 24-27, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30370576

RESUMO

Natural products and derivatives thereof are of considerable importance in the discovery of new pharmaceuticals, for example, for the treatment of cancer, diabetes, inflammation diseases, and infection diseases caused by bacteria, fungi, viruses, or parasites. The great biodiversity of marine microorganisms is reflected in their huge chemical diversity, which provides a rich source of biologically active compounds. An increasing interest in marine microorganisms as promising producers of new compounds with potential medical applications has raised increasing interest in the sustainable exploration of marine microbial resources for the discovery of new antibiotics, which is highlighted. The bottlenecks in the development of drugs using the large marine natural product pipeline are also discussed.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Organismos Aquáticos , Produtos Biológicos/farmacologia , Animais , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Organismos Aquáticos/isolamento & purificação , Organismos Aquáticos/microbiologia , Bactérias/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/fisiologia , Farmacorresistência Fúngica/efeitos dos fármacos , Farmacorresistência Fúngica/fisiologia , Fungos/isolamento & purificação , Humanos
16.
Sci Rep ; 8(1): 16290, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30389965

RESUMO

Marine infrastructure can favor the spread of non-indigenous marine biofouling species by providing a suitable habitat for them to proliferate. Cryptic organisms or those in early life stages can be difficult to distinguish by conventional morphological taxonomy. Molecular tools, such as metabarcoding, may improve their detection. In this study, the ability of morpho-taxonomy and metabarcoding (18S rRNA and COI) using three reference databases (PR2, BOLD and NCBI) to characterize biodiversity and detect non-indigenous species (NIS) in biofouling was compared on 60 passive samplers deployed over summer and winter in a New Zealand marina. Highest resolution of metazoan taxa was identified using 18S rRNA assigned to PR2. There were higher assignment rates to NCBI reference sequences, but poorer taxonomic identification. Using all methods, 48 potential NIS were identified. Metabarcoding detected the largest proportion of those NIS: 77% via 18S rRNA/PR2 and NCBI and 35% via COI/BOLD and NCBI. Morpho-taxonomy detected an additional 14% of all identified NIS comprising mainly of bryozoan taxa. The data highlight several on-going challenges, including: differential marker resolution, primer biases, incomplete sequence reference databases, and variations in bioinformatic pipelines. Combining morpho-taxonomy and molecular analysis methods will likely enhance the detection of NIS from complex biofouling.


Assuntos
Organismos Aquáticos/isolamento & purificação , Incrustação Biológica , Espécies Introduzidas , Microbiota/genética , Animais , Organismos Aquáticos/genética , Biodiversidade , Código de Barras de DNA Taxonômico/métodos , Bases de Dados Genéticas/estatística & dados numéricos , Metagenoma/genética , Metagenômica/métodos , Nova Zelândia , Filogenia , RNA Ribossômico 18S/genética
17.
Protist ; 169(6): 826-852, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30453272

RESUMO

Archigregarines are a key group for understanding the early evolution of Apicomplexa. Here we report morphological, ultrastructural, and molecular phylogenetic evidence from two archigregarine species: Selenidium pygospionis sp. n. and S. pherusae sp. n. They exhibited typical features of archigregarines. Additionally, an axial row of vacuoles of a presumably nutrient distribution system was revealed in S. pygospionis. Intracellular stages of S. pygospionis found in the host intestinal epithelium may point to the initial intracellular localization in the course of parasite development. Available archigregarine SSU (18S) rDNA sequences formed four major lineages fitting the taxonomical affiliations of their hosts, but not the morphological or biological features used for the taxonomical revision by Levine (1971). Consequently, the genus Selenidioides Levine, 1971 should be abolished. The branching order of these lineages was unresolved; topology tests rejected neither para- nor monophyly of archigregarines. We provided phylogenies based on LSU (28S) rDNA and near-complete ribosomal operon (concatenated SSU, 5.8S, LSU rDNAs) sequences including S. pygospionis sequences. Although being preliminary, they nevertheless revealed the monophyly of gregarines previously challenged by many molecular phylogenetic studies. Despite their molecular-phylogenetic heterogeneity, archigregarines exhibit an extremely conservative plesiomorphic structure; their ultrastructural key features appear to be symplesiomorphies rather than synapomorphies.


Assuntos
Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Filogenia , Animais , Apicomplexa/genética , Apicomplexa/ultraestrutura , Organismos Aquáticos/genética , Organismos Aquáticos/ultraestrutura , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Locomoção , Microscopia , Microscopia Eletrônica , Poliquetos/parasitologia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA
20.
Nature ; 560(7716): 92-96, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30046108

RESUMO

Global warming is markedly changing diverse coral reef ecosystems through an increasing frequency and magnitude of mass bleaching events1-3. How local impacts scale up across affected regions depends on numerous factors, including patchiness in coral mortality, metabolic effects of extreme temperatures on populations of reef-dwelling species4 and interactions between taxa. Here we use data from before and after the 2016 mass bleaching event to evaluate ecological changes in corals, algae, fishes and mobile invertebrates at 186 sites along the full latitudinal span of the Great Barrier Reef and western Coral Sea. One year after the bleaching event, reductions in live coral cover of up to 51% were observed on surveyed reefs that experienced extreme temperatures; however, regional patterns of coral mortality were patchy. Consistent declines in coral-feeding fishes were evident at the most heavily affected reefs, whereas few other short-term responses of reef fishes and invertebrates could be attributed directly to changes in coral cover. Nevertheless, substantial region-wide ecological changes occurred that were mostly independent of coral loss, and instead appeared to be linked directly to sea temperatures. Community-wide trophic restructuring was evident, with weakening of strong pre-existing latitudinal gradients in the diversity of fishes, invertebrates and their functional groups. In particular, fishes that scrape algae from reef surfaces, which are considered to be important for recovery after bleaching2, declined on northern reefs, whereas other herbivorous groups increased on southern reefs. The full impact of the 2016 bleaching event may not be realized until dead corals erode during the next decade5,6. However, our short-term observations suggest that the recovery processes, and the ultimate scale of impact, are affected by functional changes in communities, which in turn depend on the thermal affinities of local reef-associated fauna. Such changes will vary geographically, and may be particularly acute at locations where many fishes and invertebrates are close to their thermal distribution limits7.


Assuntos
Antozoários/fisiologia , Organismos Aquáticos/fisiologia , Biodiversidade , Recifes de Corais , Aquecimento Global , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Peixes/fisiologia , Oceanos e Mares , Dinâmica Populacional , Água do Mar/análise , Temperatura Ambiente
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