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1.
PLoS One ; 15(9): e0238405, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32936809

RESUMO

In the California Current Ecosystem, El Niño acts as a natural phenomenon that is partially representative of climate change impacts on marine bacteria at timescales relevant to microbial communities. Between 2014-2016, the North Pacific warm anomaly (a.k.a., the "blob") and an El Niño event resulted in prolonged ocean warming in the Southern California Bight (SCB). To determine whether this "marine heatwave" resulted in shifts in microbial populations, we sequenced the rpoC1 gene from the biogeochemically important picocyanobacteria Prochlorococcus and Synechococcus at 434 time points from 2009-2018 in the MICRO time series at Newport Beach, CA. Across the time series, we observed an increase in the abundance of Prochlorococcus relative to Synechococcus as well as elevated frequencies of ecotypes commonly associated with low-nutrient and high-temperature conditions. The relationships between environmental and ecotype trends appeared to operate on differing temporal scales. In contrast to ecotype trends, most microdiverse populations were static and possibly reflect local habitat conditions. The only exceptions were microdiversity from Prochlorococcous HLI and Synechococcus Clade II that shifted in response to the 2015 El Niño event. Overall, Prochlorococcus and Synechococcus populations did not return to their pre-heatwave composition by the end of this study. This research demonstrates that extended warming in the SCB can result in persistent changes in key microbial populations.


Assuntos
El Niño Oscilação Sul , Prochlorococcus/isolamento & purificação , Água do Mar/microbiologia , Synechococcus/isolamento & purificação , Organismos Aquáticos/genética , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Biodiversidade , California , Mudança Climática , Ecossistema , Ecótipo , Genes Bacterianos , Microbiota/genética , Oceano Pacífico , Filogenia , Prochlorococcus/genética , Prochlorococcus/crescimento & desenvolvimento , Estações do Ano , Synechococcus/genética , Synechococcus/crescimento & desenvolvimento , Temperatura
2.
PLoS One ; 15(8): e0236077, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780731

RESUMO

As aquatic invasive species (AIS) proliferate worldwide, a better understanding of their roles in invaded habitats is needed to inform management and introduction prevention strategies and priorities. Metabarcoding of stomach content DNA (scDNA) shows considerable promise in such regard. We thus metabarcoded scDNA from two non-native fish species (alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax)), and three native ones (bloater (Coregonus hoyi), ninespine stickleback (Pungitius pungitius), and slimy sculpin (Cottus cognatus)). Fishes (N = 376) were sampled in spring 2009 and 2010 from 73-128 m depths at three Lake Michigan sites. Four mitochondrial cytochrome oxidase 1 (CO1) primer sets designed to target five potential AIS prey, and a universal aquatic invertebrate CO1 primer set targeting both native and AIS prey were used. Quality controlled prey amplicons were matched to three AIS prey: Bythotrephes longimanus (mean percent frequency occurrence, all samples = 7%), Cercopagis pengoi (5%), and Dreissena rostriformis bugensis (11%). Neither invasive prey Dreissena polymorpha nor Hemimysis anomala were detected. Native prey Leptodiaptomus sicilis, Limnocalanus macrurus, and Mysis diluviana were relatively common in scDNA (respective mean percent occurrences, all samples: 48%, 25%, 42%). Analysis of variation in prey occurrences for sample site, predator species, sample year, sample depth, and predator total length (TL) indicated site and predator species were most important. However, B. longimanus occurrence in scDNA depended upon predator TL, perhaps indicative of its unique defensive spine limiting susceptibility to predation until fishes exceed species-specific gape-based limitations. Our analysis of native and invasive prey species indicated possible indirect AIS impacts such as native predators switching their diet due to AIS-driven losses of preferred native prey. Metabarcoding demonstrated that AIS are integrated components of the offshore Lake Michigan food web, with both native and non-native predators, and both invasive and native prey are affecting species interactions across multiple trophic levels.


Assuntos
Organismos Aquáticos/genética , Peixes/fisiologia , Preferências Alimentares , Espécies Introduzidas , Invertebrados/genética , Animais , Organismos Aquáticos/isolamento & purificação , Código de Barras de DNA Taxonômico , Cadeia Alimentar , Conteúdo Gastrointestinal , Lagos , Michigan , Comportamento Predatório , Wisconsin
3.
Mar Drugs ; 18(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290208

RESUMO

The marine-derived fungus Aspergillus falconensis, isolated from sediment collected from the Canyon at Dahab, Red Sea, yielded two new chlorinated azaphilones, falconensins O and P (1 and 2) in addition to four known azaphilone derivatives (3-6) following fermentation of the fungus on solid rice medium containing 3.5% NaCl. Replacing NaCl with 3.5% NaBr induced accumulation of three additional new azaphilones, falconensins Q-S (7-9) including two brominated derivatives (7 and 8) together with three known analogues (10-12). The structures of the new compounds were elucidated by 1D and 2D NMR spectroscopy and HRESIMS data as well as by comparison with the literature. The absolute configuration of the azaphilone derivatives was established based on single-crystal X-ray diffraction analysis of 5, comparison of NMR data and optical rotations as well as on biogenetic considerations. Compounds 1, 3-9, and 11 showed NF-κB inhibitory activity against the triple negative breast cancer cell line MDA-MB-231 with IC50 values ranging from 11.9 to 72.0 µM.


Assuntos
Antineoplásicos/química , Organismos Aquáticos/química , Aspergillus/química , Benzopiranos/química , Sedimentos Geológicos/microbiologia , Pigmentos Biológicos/química , Animais , Antineoplásicos/farmacologia , Organismos Aquáticos/isolamento & purificação , Aspergillus/isolamento & purificação , Benzopiranos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Oceano Índico , Concentração Inibidora 50 , Pigmentos Biológicos/farmacologia
4.
Microbiol Res ; 233: 126410, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945517

RESUMO

Photobacterium species are widely distributed in the marine environment. The overall metabolism of this genus remains largely unknown. In order to improve our knowledge on this bacterium, the relationship between the genome and phenome of the Photobacterium isolate was analyzed. The cream colored, Gram-negative, rod-shaped and motile bacterial strain, J15, was isolated from marine water of Tanjung Pelepas, Johor, Malaysia. The 5,684,538 bp genome of strain J15 comprised 3 contigs (2 chromosomes and 1 plasmid) with G + C content of 46.39 % and contained 4924 protein-coding genes including 180 tRNAs and 40 rRNAs. The phenotypic microarray (PM) as analyzed using BIOLOG showed the utilization of; i) 93 of the 190 carbon sources tested, where 61 compounds were used efficiently; ii) 41 of the 95 nitrogen sources tested, where 22 compounds were used efficiently; and iii) 3 of the 94 phosphorous and sulphur sources tested. Furthermore, high tolerance to osmotic stress, basic pH and toxic compounds as well as resistance to antibiotics of strain J15 were determined by BIOLOG PM. The ANI and kSNP analyses revealed that strain J15 to be the same species with Photobacterium marinum AK15 with ANI value of 96.93 % and bootstrapping value of 100 in kSNP. Based on the ANI and kSNP analyses, strain J15 was identified as P. marinum J15.


Assuntos
Organismos Aquáticos/classificação , Genoma Bacteriano , Photobacterium/classificação , Filogenia , Água do Mar/microbiologia , Organismos Aquáticos/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Genômica , Malásia , Fenômica , Photobacterium/metabolismo , Análise de Sequência de DNA
5.
Mar Drugs ; 18(2)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979232

RESUMO

Microbial co-cultivation is employed for awakening silent biosynthetic gene clusters (BGCs) to enhance chemical diversity. However, the selection of appropriate partners for co-cultivation remains a challenge. Furthermore, competitive interactions involving the suppression of BGCs or upregulation of known, functional metabolite(s) during co-cultivation efforts is also common. Herein, we performed an alternative approach for targeted selection of the best co-cultivation pair. Eight marine sediment-derived fungi were classified as strong or weak, based on their anti-phytopathogenic potency. The fungi were co-cultured systematically and analyzed for their chemical profiles and anti-phytopathogenic activity. Based on enhanced bioactivity and a significantly different metabolite profile including the appearance of a co-culture specific cluster, the co-culture of Plenodomus influorescens (strong) and Pyrenochaeta nobilis (weak) was prioritized for chemical investigation. Large-scale co-cultivation resulted in isolation of five polyketide type compounds: two 12-membered macrolides, dendrodolide E (1) and its new analog dendrodolide N (2), as well as two rare azaphilones spiciferinone (3) and its new analog 8a-hydroxy-spiciferinone (4). A well-known bis-naphtho-γ-pyrone type mycotoxin, cephalochromin (5), whose production was specifically enhanced in the co-culture, was also isolated. Chemical structures of compounds 1-5 were elucidated by NMR, HRMS and [] analyses. Compound 5 showed the strongest anti-phytopathogenic activity against Xanthomonas campestris and Phytophthora infestans with IC50 values of 0.9 and 1.7 µg/mL, respectively.


Assuntos
Agroquímicos/metabolismo , Organismos Aquáticos/metabolismo , Produtos Biológicos/metabolismo , Fungos/metabolismo , Microbiologia Industrial/métodos , Agroquímicos/química , Agroquímicos/isolamento & purificação , Agroquímicos/farmacologia , Organismos Aquáticos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Técnicas de Cocultura/métodos , Fungos/isolamento & purificação , Sedimentos Geológicos/microbiologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Metabolômica , Phytophthora infestans/efeitos dos fármacos , Policetídeos/isolamento & purificação , Policetídeos/metabolismo , Projetos de Pesquisa , Xanthomonas campestris/efeitos dos fármacos
6.
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
7.
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
8.
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
9.
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
10.
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
11.
Microbiologyopen ; 8(9): e00835, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31318499

RESUMO

Marine Vibrio members are of great interest for both ecological and biotechnological research, which often relies on their isolation. Whereas many efforts have been made for the detection of food-borne pathogenic species, much less is known about the performances of standard culture media toward environmental vibrios. We show that the isolation/enumeration of marine vibrios using thiosulfate-citrate-bile salts-sucrose agar (TCBS) as selective medium may be hampered by the variable adaptability of different taxa to the medium, which may result even in isolation failure and/or in substantial total count underestimation. We propose a modified TCBS as isolation medium, adjusted for marine vibrios requirements, which greatly improved their recovery in dilution plate counts, compared with the standard medium. The modified medium offers substantial advantages over TCBS, providing more accurate and likely estimations of the actual presence of vibrios. Modified TCBS allowed the recovery of otherwise undetected vibrios, some of which producing biotechnologically valuable enzymes, thus expanding the isolation power toward potentially new enzyme-producers Vibrio taxa. Moreover, we report a newly designed Vibrio-specific PCR primers pair, targeting a unique rpoD sequence, useful for rapid confirmation of isolates as Vibrio members and subsequent genetic analyses.


Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/isolamento & purificação , Técnicas Bacteriológicas/métodos , Meios de Cultura/química , Vibrio/crescimento & desenvolvimento , Vibrio/isolamento & purificação
12.
Antonie Van Leeuwenhoek ; 112(11): 1691-1697, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31289978

RESUMO

A novel Gram-stain negative, strictly aerobic, rod-shaped motile bacterium with a single flagellum, designated strain DASS28T, was isolated from surface sediment of Bohai Sea in China. Growth occurred in the presence of 1.0-4.0% NaCl (w/v, optimum 2.0%), at 10-37 °C (optimum 20 °C) on the Marine agar 2216E and pH 6.0-10.0 (optimum pH 8.0). The major fatty acids (> 10% of total fatty acids) were summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH), C16:0 and C18:1ω7c. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, an unidentified aminolipid and two unidentified polar lipids. The major respiratory quinone was ubiquinone-8 (Q-8). The genomic DNA G + C content calculated from the genome sequence of strain DASS28T was 48.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain DASS28T belongs to the genus Corallincola and shows high 16S rRNA gene sequence similarity of 96.7% to Corallincola platygyrae JLT 2006T (= JCM18796T = CGMCC 1.10992T). On the basis of the polyphasic evidence, strain DASS28T is considered to represent a novel species in the genus Corallincola, for which the name Corallincola luteus sp. nov. is proposed. The type strain is DASS28T (= KCTC 52376T = MCCC 1K03208T).


Assuntos
Organismos Aquáticos/classificação , Organismos Aquáticos/isolamento & purificação , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Sedimentos Geológicos/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia
13.
Nature ; 570(7761): 372-375, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31118509

RESUMO

The ocean-the Earth's largest ecosystem-is increasingly affected by anthropogenic climate change1,2. Large and globally consistent shifts have been detected in species phenology, range extension and community composition in marine ecosystems3-5. However, despite evidence for ongoing change, it remains unknown whether marine ecosystems have entered an Anthropocene6 state beyond the natural decadal to centennial variability. This is because most observational time series lack a long-term baseline, and the few time series that extend back into the pre-industrial era have limited spatial coverage7,8. Here we use the unique potential of the sedimentary record of planktonic foraminifera-ubiquitous marine zooplankton-to provide a global pre-industrial baseline for the composition of modern species communities. We use a global compilation of 3,774 seafloor-derived planktonic foraminifera communities of pre-industrial age9 and compare these with communities from sediment-trap time series that have sampled plankton flux since AD 1978 (33 sites, 87 observation years). We find that the Anthropocene assemblages differ from their pre-industrial counterparts in proportion to the historical change in temperature. We observe community changes towards warmer or cooler compositions that are consistent with historical changes in temperature in 85% of the cases. These observations not only confirm the existing evidence for changes in marine zooplankton communities in historical times, but also demonstrate that Anthropocene communities of a globally distributed zooplankton group systematically differ from their unperturbed pre-industrial state.


Assuntos
Organismos Aquáticos/isolamento & purificação , Mudança Climática/estatística & dados numéricos , Ecossistema , Foraminíferos/isolamento & purificação , Plâncton/isolamento & purificação , Animais , Organismos Aquáticos/classificação , Foraminíferos/classificação , Sedimentos Geológicos/química , História do Século XIX , História do Século XX , História do Século XXI , Oceanos e Mares , Plâncton/classificação , Água do Mar/análise , Temperatura , Zooplâncton/classificação , Zooplâncton/isolamento & purificação
14.
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
15.
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
16.
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
17.
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 , Chlorocebus aethiops , 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
18.
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
19.
Environ Microbiol Rep ; 11(3): 275-286, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30924315

RESUMO

Understanding of community ecology is scale dependent. When the scale definition changes from subjectively defined "regional species pools" to "habitat species pools", heterogeneity differences occur for microbial communities. However, given the environmental gradients differences among habitats, responses of other organisms and interspecific correlations to habitat species pools may also be heterogeneous. This hypothesis is supported by our research about algal and bacterial communities among four different habitats in littoral zones. In our results, both the algal and bacterial community compositions varied along habitat species pools. Furthermore, at community level, significant correlation was only found between bacterioplankton and phytoplankton in pelagic habitat. And at individual level, the covariant trends between habitat generalists in algal and bacterial communities varied among habitats. Our results indicated that habitat-specific patterns can not only influence the habitat species pools, but also shape the interspecies interaction, and this should be considered in the further study of algae-bacterial correlation.


Assuntos
Organismos Aquáticos/classificação , Bactérias/classificação , Biodiversidade , Ecossistema , Organismos Aquáticos/genética , Organismos Aquáticos/isolamento & purificação , Bactérias/genética , Bactérias/isolamento & purificação , Biota , Lagos/microbiologia , Interações Microbianas , Microbiologia da Água
20.
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
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