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1.
Nat Commun ; 11(1): 4658, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938931

RESUMO

Dimethylsulfoniopropionate (DMSP) is an important marine osmolyte. Aphotic environments are only recently being considered as potential contributors to global DMSP production. Here, our Mariana Trench study reveals a typical seawater DMSP/dimethylsulfide (DMS) profile, with highest concentrations in the euphotic zone and decreased but consistent levels below. The genetic potential for bacterial DMSP synthesis via the dsyB gene and its transcription is greater in the deep ocean, and is highest in the sediment.s DMSP catabolic potential is present throughout the trench waters, but is less prominent below 8000 m, perhaps indicating a preference to store DMSP in the deep for stress protection. Deep ocean bacterial isolates show enhanced DMSP production under increased hydrostatic pressure. Furthermore, bacterial dsyB mutants are less tolerant of deep ocean pressures than wild-type strains. Thus, we propose a physiological function for DMSP in hydrostatic pressure protection, and that bacteria are key DMSP producers in deep seawater and sediment.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Água do Mar/química , Água do Mar/microbiologia , Compostos de Sulfônio/metabolismo , Bactérias/isolamento & purificação , Clorofila A/análise , Clorofila A/metabolismo , Genes Bacterianos , Sedimentos Geológicos/química , Pressão Hidrostática , Marinobacter/genética , Marinobacter/isolamento & purificação , Marinobacter/metabolismo , Metagenoma , Mutação , Oceanos e Mares , Prochlorococcus/genética , Prochlorococcus/isolamento & purificação , Prochlorococcus/metabolismo , RNA Ribossômico 16S , Sulfetos/análise , Sulfetos/metabolismo , Compostos de Sulfônio/análise , Synechococcus/genética , Synechococcus/isolamento & purificação , Synechococcus/metabolismo
2.
PLoS One ; 15(8): e0236246, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804956

RESUMO

K+ is an essential nutrient for plant growth and is responsible for many important physiological processes. K+ deficiency leads to crop yield losses, and overexpression of K+ transporter genes has been proven to be an effective way to resolve this problem. However, current research on the overexpression of K+ transporter genes is limited to plant sources. TrkH is a bacterial K+ transporter whose function generally depends on the regulation of TrkA. To date, whether TrkH can improve K+ uptake in eukaryotic organisms is still unknown. In this study, a novel MbtrkH gene was cloned from marine microbial metagenomic DNA. Functional complementation and K+-depletion analyses revealed that MbTrkH functions in K+ uptake in the K+-deficient yeast strain CY162. Moreover, K+-depletion assays revealed that MbtrkH overexpression improves plant K+ uptake. K+ hydroponic culture experiments showed that, compared with WT tobacco lines, MbtrkH transgenic tobacco lines had significantly greater fresh weights, dry weights and K+ contents. These results indicate that MbTrkH promotes K+ uptake independently of TrkA in eukaryotes and provide a new strategy for improving K+-use efficiency in plants.


Assuntos
Organismos Aquáticos/genética , Potássio/metabolismo , Saccharomyces cerevisiae/metabolismo , Água do Mar/microbiologia , Tabaco/metabolismo , Clonagem Molecular , Metagenoma , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Canais de Potássio/genética , Canais de Potássio/metabolismo , Saccharomyces cerevisiae/genética , Tabaco/genética
3.
PLoS One ; 15(8): e0234839, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853201

RESUMO

Distinct lineages of Gammaproteobacteria clade Woeseiales are globally distributed in marine sediments, based on metagenomic and 16S rRNA gene analysis. Yet little is known about why they are dominant or their ecological role in Arctic fjord sediments, where glacial retreat is rapidly imposing change. This study combined 16S rRNA gene analysis, metagenome-assembled genomes (MAGs), and genome-resolved metatranscriptomics uncovered the in situ abundance and transcriptional activity of Woeseiales with burial in four shallow sediment sites of Kongsfjorden and Van Keulenfjorden of Svalbard (79°N). We present five novel Woeseiales MAGs and show transcriptional evidence for metabolic plasticity during burial, including sulfur oxidation with reverse dissimilatory sulfite reductase (dsrAB) down to 4 cm depth and nitrite reduction down to 6 cm depth. A single stress protein, spore protein SP21 (hspA), had a tenfold higher mRNA abundance than any other transcript, and was a hundredfold higher on average than other transcripts. At three out of the four sites, SP21 transcript abundance increased with depth, while total mRNA abundance and richness decreased, indicating a shift in investment from metabolism and other cellular processes to build-up of spore protein SP21. The SP21 gene in MAGs was often flanked by genes involved in membrane-associated stress response. The ability of Woeseiales to shift from sulfur oxidation to nitrite reduction with burial into marine sediments with decreasing access to overlying oxic bottom waters, as well as enter into a dormant state dominated by SP21, may account for its ubiquity and high abundance in marine sediments worldwide, including those of the rapidly shifting Arctic.


Assuntos
Gammaproteobacteria/genética , Sedimentos Geológicos/microbiologia , Regiões Árticas , Proteínas de Bactérias/genética , Estuários , Gammaproteobacteria/classificação , Gammaproteobacteria/metabolismo , Genoma Bacteriano , Proteínas de Choque Térmico/genética , Metagenoma , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Svalbard , Transcriptoma
4.
PLoS One ; 15(8): e0236822, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764772

RESUMO

Various marine fungi have been shown to produce interesting, bioactive compounds, but scaling up the production of these compounds can be challenging, particularly because little is generally known about how the producing organisms grow. Here we assessed the suitability of using 100-well BioScreen plates or 96-well plates incubated in a robot hotel to cultivate eight filamentous marine fungi, six sporulating and two non-sporulating, to obtain data on growth and substrate (glucose, xylose, galactose or glycerol) utilisation in a high throughput manner. All eight fungi grew in both cultivation systems, but growth was more variable and with more noise in the data in the Cytomat plate hotel than in the BioScreen. Specific growth rates between 0.01 (no added substrate) and 0.07 h-1 were measured for strains growing in the BioScreen and between 0.01 and 0.27 h-1 for strains in the plate hotel. Three strains, Dendryphiella salina LF304, Penicillium chrysogenum KF657 and Penicillium pinophilum LF458, consistently had higher specific growth rates on glucose and xylose in the plate hotel than in the BioScreen, but otherwise results were similar in the two systems. However, because of the noise in data from the plate hotel, the data obtained from it could only be used to distinguish between substrates which did or did not support growth, whereas data from BioScreen also provided information on substrate preference. Glucose was the preferred substrate for all strains, followed by xylose and galactose. Five strains also grew on glycerol. Therefore it was important to minimise the amount of glycerol introduced with the inoculum to avoid misinterpreting the results for growth on poor substrates. We concluded that both systems could provide physiological data with filamentous fungi, provided sufficient replicates are included in the measurements.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Água do Mar/microbiologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/isolamento & purificação , Meios de Cultura/química , Meios de Cultura/farmacologia , Glucose/farmacologia , Glicerol/farmacologia , Penicillium/efeitos dos fármacos , Penicillium/isolamento & purificação , Xilose/farmacologia
5.
Nat Commun ; 11(1): 3941, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770005

RESUMO

Anaerobic oxidation of methane (AOM) mediated by anaerobic methanotrophic archaea (ANME) is the primary process that provides energy to cold seep ecosystems by converting methane into inorganic carbon. Notably, cold seep ecosystems are dominated by highly divergent heterotrophic microorganisms. The role of the AOM process in supporting heterotrophic population remains unknown. We investigate the acetogenic capacity of ANME-2a in a simulated cold seep ecosystem using high-pressure biotechnology, where both AOM activity and acetate production are detected. The production of acetate from methane is confirmed by isotope-labeling experiments. A complete archaeal acetogenesis pathway is identified in the ANME-2a genome, and apparent acetogenic activity of the key enzymes ADP-forming acetate-CoA ligase and acetyl-CoA synthetase is demonstrated. Here, we propose a modified model of carbon cycling in cold seeps: during AOM process, methane can be converted into organic carbon, such as acetate, which further fuels the heterotrophic community in the ecosystem.


Assuntos
Acetatos/metabolismo , Archaea/enzimologia , Proteínas de Bactérias/metabolismo , Coenzima A Ligases/metabolismo , Metano/metabolismo , Anaerobiose , Archaea/genética , Proteínas de Bactérias/genética , Ciclo do Carbono/fisiologia , Coenzima A Ligases/genética , Genoma Arqueal , Sedimentos Geológicos/microbiologia , Redes e Vias Metabólicas/genética , Oxirredução , Água do Mar/microbiologia
6.
PLoS One ; 15(8): e0237704, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804963

RESUMO

Since plastics degrade very slowly, they remain in the environment on much longer timescales than most natural organic substrates and provide a novel habitat for colonization by bacterial communities. The spectrum of relationships between plastics and bacteria, however, is little understood. The first objective of this study was to examine plastics as substrates for communities of Bacteria in estuarine surface waters. We used next-generation sequencing of the 16S rRNA gene to characterize communities from plastics collected in the field, and over the course of two colonization experiments, from biofilms that developed on plastic (low-density polyethylene, high-density polyethylene, polypropylene, polycarbonate, polystyrene) and glass substrates placed in the environment. Both field sampling and colonization experiments were conducted in estuarine tributaries of the lower Chesapeake Bay. As a second objective, we concomitantly analyzed biofilms on plastic substrates to ascertain the presence and abundance of Vibrio spp. bacteria, then isolated three human pathogens, V. cholerae, V. parahaemolyticus, and V. vulnificus, and determined their antibiotic-resistant profiles. In both components of this study, we compared our results with analyses conducted on paired samples of estuarine water. This research adds to a nascent literature that suggests environmental factors govern the development of bacterial communities on plastics, more so than the characteristics of the plastic substrates themselves. In addition, this study is the first to culture three pathogenic vibrios from plastics in estuaries, reinforcing and expanding upon earlier reports of plastic pollution as a habitat for Vibrio species. The antibiotic resistance detected among the isolates, coupled with the longevity of plastics in the aqueous environment, suggests biofilms on plastics have potential to persist and serve as focal points of potential pathogens and horizontal gene transfer.


Assuntos
Biofilmes/efeitos dos fármacos , Estuários , Plásticos , Vibrio/isolamento & purificação , Poluentes da Água , Antibacterianos/farmacologia , Oceano Atlântico , DNA Bacteriano/isolamento & purificação , Farmacorresistência Bacteriana/genética , Transferência Genética Horizontal , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Vibrio/efeitos dos fármacos , Vibrio/genética
7.
Int J Syst Evol Microbiol ; 70(7): 4130-4138, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32614761

RESUMO

Strain B66T was isolated from a marine water sample collected at Al Ruwais, located on the northern tip of Qatar. Cells were Gram-stain-negative, strictly aerobic and short- rod-shaped with a polar flagellum. The isolate was able to grow at 15-45 °C (optimum, 30 °C), at pH 5-11 (optimum, pH 6.5-8) and with 0-6 % NaCl. 16S rRNA gene sequence analysis revealed that strain B66T was affiliated with the family Alteromonadaceae, sharing the highest sequence similarities to the genera Alteromonas (93.7-95.4 %), Aestuariibacter (94.0-95.1 %), Agaribacter (93.3-93.7 %), Glaciecola (92.0-93.7 %), Marisendiminitalea (93.2-93.3 %) and Planctobacterium (92.9 %). In the phylogenetic trees, strain B66T demonstrated the novel organism formed a distinct lineage closely associated with Aestuariibacter and Planctobacterium. Major fatty acids were C16 : 0, summed feature 3 (C16 : 1 ω7c/C16 : 1 ω6c/iso-C15 : 0 2-OH and iso-C15 : 0 3-OH. The major respiratory quinone was ubiquinone-8 and the major polar lipids are phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content derived from the genome was 43.2 mol%. Based on the phenotypic, chemotaxonomic, phylogenetic and genomic data, strain B66T is considered to represent a novel species and genus for which the name Ningiella ruwaisensis gen. nov., sp. nov., is proposed. The type strain is B66T (=QCC B003/17T=LMG 30288 T=CCUG 70703T).


Assuntos
Alteromonadaceae/classificação , Filogenia , Água do Mar/microbiologia , Alteromonadaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Catar , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
8.
Int J Syst Evol Microbiol ; 70(7): 4280-4284, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32618558

RESUMO

A taxonomic study was carried out on strain PA15-N-34T, which was isolated from deep-sea sediment of Pacific Ocean. The bacterium was Gram-stain-positive, oxidase- and catalase-positive and rod-shaped. Growth was observed at salinity of 0-15.0% NaCl and at temperatures of 10-45 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PA15-N-34T belonged to the genus Alcanivorax, with the highest sequence similarity to Alcanivorax profundi MTEO17T (97.7 %), followed by Alcanivorax nanhaiticus 19 m-6T (97.3 %) and 12 other species of the genus Alcanivorax (93.4 %-97.0 %). The average nucleotide identity and DNA-DNA hybridization values between strain PA15-N-34T and type strains of the genus Alcanivorax were 71.46-81.78% and 18.7-25.2 %, respectively. The principal fatty acids (>10 %) were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c; 31.2 %), C16 : 0 (25.0 %) and summed feature 3 (14.6 %). The DNA G+C content was 57.15 mol%. The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, four unidentified aminolipids and three unidentified lipids. The novel strain can be differentiated from its closest type strain by a negative test for urease and the presence of diphosphatidylglycerol and aminolipid. The combined genotypic and phenotypic data show that strain PA15-N-34T represents a novel species within the genus Alcanivorax, for which the name Alcanivorax sediminis sp. nov. is proposed, with the type strain PA15-N-34T (=MCCC 1A14738T=KCTC 72163T).


Assuntos
Alcanivoraceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alcanivoraceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Salinidade , Análise de Sequência de DNA , Temperatura
9.
Int J Syst Evol Microbiol ; 70(8): 4698-4703, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32701426

RESUMO

A Gram-stain-negative, non-motile, facultatively anaerobic and rod-shaped bacterial strain, designated PAMC 28131T, was isolated from a sea surface microlayer sample in the open water of the Pacific Ocean. Phylogenetic analysis of the 16S rRNA gene sequence of strain PAMC 28131T revealed an affiliation to the genus Sandaracinobacter with the closest species Sandaracinobacter sibiricus RB16-17T (sequence similarity of 98.2 %). Strain PAMC 28131T was able to grow optimally with 0.5-1.0 % NaCl and at pH 6.5-7.0 and 30 °C. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, an unidentified aminolipid, an unidentified glycolipid and an unidentified lipid. The major cellular fatty acids (>10 %) were C18 : 1 ω6c and/or C18 : 1 ω7c, (42.6 %), C17 : 1 ω6c (19.3 %) and C16 : 1 ω6c and/or C16 : 1 ω7c (15.8 %), and the respiratory quinone was Q-10. The genomic DNA G+C content was 65.3 mol%. The phylogenetic, phenotypic and chemotaxonomic data showed that strain PAMC 28131T could be clearly distinguished from S. sibiricus RB16-17T. Thus, strain PAMC 28131T should be classified as representing a novel species in the genus Sandaracinobacter, for which the name Sandaracinobacter neustonicus sp. nov. is proposed. The type strain is PAMC 28131T (=KCCM 43127T=JCM 30734T).


Assuntos
Filogenia , Água do Mar/microbiologia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonadaceae/isolamento & purificação
10.
PLoS One ; 15(7): e0227395, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32628681

RESUMO

The FluidFM enables the immobilization of single cells on a hollow cantilever using relative underpressure. In this study, we systematically optimize versatile measurement parameters (setpoint, z-speed, z-length, pause time, and relative underpressure) to improve the quality of force-distance curves recorded with a FluidFM. Using single bacterial cells (here the gram negative seawater bacterium Paracoccus seriniphilus and the gram positive bacterium Lactococcus lactis), we show that Single Cell Force Spectroscopy experiments with the FluidFM lead to comparable results to a conventional Single Cell Force Spectroscopy approach using polydopamine for chemical fixation of a bacterial cell on a tipless cantilever. Even for the bacterium Lactococcus lactis, which is difficult to immobilze chemically (like seen in an earlier study), immobilization and the measurement of force-distance curves are possible by using the FluidFM technology.


Assuntos
Aderência Bacteriana , Lactococcus lactis/fisiologia , Microscopia de Força Atômica/métodos , Paracoccus/fisiologia , Células Imobilizadas/fisiologia , Vidro/química , Indóis/química , Polímeros/química , Água do Mar/microbiologia , Análise de Célula Única , Propriedades de Superfície , Titânio/química
11.
Int J Syst Evol Microbiol ; 70(8): 4555-4561, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32721276

RESUMO

A yellowish-brown-coloured bacterium, designated strain JGD-17T, was isolated from a tidal flat of Janggu-do, Garorim bay, Taean-gun, Chungcheongbuk-do, Republic of Korea. Cells were Gram-stain-negative, aerobic, non-flagellated and long-rod-shaped. Growth was observed at 20-45 °C (optimum, 25-30 °C), at pH 6.0-10.0 (9.0) and with 1-5 % (w/v) NaCl (1-3 %). Results of 16S rRNA gene sequence analysis indicated that strain JGD-17T was closely related to Muricauda nanhaiensis SM1704T (96.1 %), Muricauda olearia CL-SS4T (95.0 %), Muricauda beolgyonensis BB-My12T (94.9 %), Muricauda marina H19-56T (94.7 %) and Muricauda indica 3PC125-7T (94.5 %). The ranges of values for the average nucleotide identity and digital DNA-DNA hybridization analyses with related strains were 71.3-74.1 % and 16.9-18.2 %. The genomic DNA G+C content was 41.1 mol%. Phylogenetic analysis using the neighbour-joining method showed that strain JGD-17T formed a clade with Muricauda nanhaiensis SM1704T, Muricauda lutaonensis CC-HSB-11T, Muricauda lutea CSW06T and Muricauda pacifica SM027T. The major fatty acids were iso-C15 : 0 (26.9 %), iso-C15 : 1 G (19.5 %) and iso-C17 : 0 3-OH (12.7 %). The predominant respiratory quinone was menaquinone-6. The polar lipids were phosphatidylethanolamine, an unidentified aminolipid, an unidentified phospholipid and two unidentified lipids. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain JGD-17T represents a novel species within the genus Muricauda, for which the name Muricauda ochracea sp. nov. is proposed. The type strain is JGD-17T (=KCTC 72732T=KACC 21486T=JCM 33817T).


Assuntos
Flavobacteriaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
12.
PLoS One ; 15(7): e0235441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614866

RESUMO

Although seagrasses are economically and ecologically critical species, little is known about their blade surface microbial communities and how these communities relate to the plant host. To determine microbial community composition and diversity on seagrass blade surfaces and in the surrounding seawater,16S rRNA gene sequencing (iTag) was used for samples collected at five sites along a gradient of freshwater input in the northern Gulf of Mexico on three separate sampling dates. Additionally, seagrass surveys were performed and environmental parameters were measured to characterize host characteristics and the abiotic conditions at each site. Results showed that Thalassia testudinum (turtle grass) blades hosted unique microbial communities that were distinct in composition and diversity from the water column. Environmental conditions, including water depth, salinity, and temperature, influenced community structure as blade surface microbial communities varied among sites and sampling dates in correlation with changes in environmental parameters. Microbial community composition also correlated with seagrass host characteristics, including growth rates and blade nutrient composition. There is some evidence for a core community for T. testudinum as 21 microorganisms from five phyla (Cyanobacteria, Proteobacteria, Planctomycetes, Chloroflexi, and Bacteroidetes) were present in all blade surface samples. This study provides new insights and understanding of the processes that influence the structure of marine phyllosphere communities, how these microbial communities relate to their host, and their role as a part of the seagrass holobiont, which is an important contribution given the current decline of seagrass coverage worldwide.


Assuntos
Bactérias/classificação , Água Doce/microbiologia , Hydrocharitaceae/microbiologia , Microbiota , Folhas de Planta/microbiologia , Água do Mar/microbiologia , Bactérias/genética , Golfo do México , Interações entre Hospedeiro e Microrganismos , Hydrocharitaceae/fisiologia , Filogenia , Folhas de Planta/fisiologia , RNA Ribossômico 16S/genética , Salinidade , Áreas Alagadas
13.
Int J Syst Evol Microbiol ; 70(8): 4562-4568, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32618560

RESUMO

A Gram-stain-negative, yellow-pigmented, non-spore-forming, non-motile, rod-shaped, catalase-positive, strictly aerobic bacterial strain, designated CAU 1491T, was isolated from seawater and its taxonomic position was examined using a polyphasic approach. Cells of strain CAU 1491T grew optimally at 30 °C, pH 7.5 and in 2.0 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence of CAU 1491T showed that it formed a distinct lineage within the family Flavobacteriaceae as a separate deep branch, with 97.0 % or lower sequence similarity to representatives of the genera Lacinutrix, Gaetbulibacter and Aquibacter. The major cellular fatty acids of strain CAU 1491T were iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH and summed feature 3. The polar lipid pattern consisted of diphosphatidylglycerol, phosphatidylserine, phosphatidylethanolamine and an unidentified phospholipid. The strain contained MK-6 as the sole respiratory quinone. Genome sequencing revealed that strain CAU 1491T has a genome size of 3.13 Mbp and a G+C content of 32.4 mol%. On the basis of the phenotypic, chemotaxonomic and genomic data, strain CAU 1491T represents a new genus and species in the family Flavobacteriaceae for which the name Pontimicrobium aquaticum gen. nov., sp. nov. is proposed. The type strain of Pontimicrobium aquaticum is CAU 1491T (=KCTC 72003T=NBRC 113695T).


Assuntos
Flavobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
Int J Syst Evol Microbiol ; 70(8): 4451-4457, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32687464

RESUMO

A novel Gram-stain-negative, straight or curved rod-shaped, non-spore-forming, strictly aerobic, motile bacterium with a single polar flagellum, designated D3211T, was isolated from marine alga collected at the seashore of Yantai, PR China. The organism grew optimally at 24 °C, pH 7.0 and in the presence of 2.0 % (w/v) NaCl. Strain D3211T contained ubiquinone 8 as the major respiratory quinone and C16 : 1 ω7c and/or C16 : 1 ω6c, C16 : 0, iso-C17 : 0 and anteiso-C17 : 1 B and/or iso-C17 : 1 I as the major fatty acids. The predominant polar lipids of strain D3211T were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content of strain D3211T was 39.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the novel strain was related most closely to Paraglaciecola arctica BSs20135T, Paraglaciecola aestuariivivens JDTF-33T, Paraglaciecola aquimarina KCTC 32108T, Paraglaciecola mesophila DSM 15026T, Paraglaciecola psychrophila JCM 13954T and Paraglaciecola polaris ARK 150T with 97.6, 97.6, 97.5, 97.4, 97.3 and 97.1 % sequence similarities, respectively. Calculated average nucleotide identity and DNA-DNAhybridization values between strain D3211T and its phylogenetically related Paraglaciecola species were in the range 70.2-73.4 % and 19.1-20.4 %, respectively. On the basis of polyphasic analyses, strain D3211T represents a novel species of the genus Paraglaciecola, for which the name Paraglaciecola marina sp. nov. is proposed. The type strain is D3211T (=KCTC 72122T=MCCC 1K03603T).


Assuntos
Alteromonadaceae/classificação , Filogenia , Sargassum/microbiologia , Alteromonadaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Ubiquinona/química
15.
Int J Syst Evol Microbiol ; 70(8): 4691-4697, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32697185

RESUMO

Strain MEBiC09520T, which was isolated from a tidal sediment in Incheon, Korea, is a pale yellow, rod-shaped bacterium, cells of which are 0.4-0.5 µm in width and 1.5-2 µm in length. Strain MEBiC09520T shared 95.17 and 92.57% 16S rRNA gene sequence similarity with Emcibacter nanhaiensis and E. congregatus, respectively. It grew optimally at pH 6.0, at 55 °C and with 2.5-3.5% (w/v) NaCl. Its polar lipid components included phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), an unidentified phospholipid (PL), three unidentified aminolipids (ALs) and two unidentified lipids (L). The fatty acids C16:0, C19:0 cyclo ω8c, C14:0 2-OH and summed feature 8 (C18:1ω7c and/or C18:1ω6c) were predominantly present in its cell wall. Strain MEBiC09520T was thermophilic, while E. nanhaiensis and E. congregatus were mesophilic. Although E. nanhaiensis showed no nitrate reduction activity, MEBiC09520T and E. congregatus showed a positive reaction. These strains differed in carbohydrate utilization. In particular, E. congregatus was able to thrive on various carbohydrate substrates as compared to the other strains. The average nucleotide identity value was 69.92% between strain MEBiC09520T and E. congregatus ZYLT, 70.38% between E. congregatus ZYLT and E. nanhaiensis HTCJW17T, and 72.83% between strain MEBiC09520 and E. nanhaiensis HTCJW17T. Considering these differences, strain MEBiC09520T (=KCCM 43320T=MCCC 1K03920T) is suggested to represent and novel species of a new genus, Luteithermobacter gelatinilyticus gen. nov., sp. nov., and E. congregatus should be reclassified as Paremcibacter congregatus gen. nov., comb. nov.


Assuntos
Alphaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
16.
Int J Syst Evol Microbiol ; 70(8): 4668-4682, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32701422

RESUMO

Ten representative actinobacterial strains isolated from marine sediments collected worldwide were studied to determine their taxonomic status. The strains were previously identified as members of the genus Salinispora and shared >99 % 16S rRNA gene sequence similarity to the three currently recognized Salinispora species. Comparative genomic analyses resulted in the delineation of six new species based on average nucleotide identity and digital DNA-DNA hybridization values below 95 and 70 %, respectively. The species status of the six new groups was supported by a core-genome phylogeny reconstructed from 2106 orthologs detected in 118 publicly available Salinispora genomes. Chemotaxonomic and physiological studies were used to complete the phenotypic characterization of the strains. The fatty acid profiles contained the major components iso-C16 : 0, C15 : 0, iso-17 : 0 and anteiso C17 : 0. Galactose and xylose were common in all whole-sugar patterns but differences were found between the six groups of strains. Polar lipid compositions were also unique for each species. Distinguishable physiological and biochemical characteristics were also recorded. The names proposed are Salinispora cortesiana sp. nov., CNY-202T (=DSM 108615T=CECT 9739T); Salinispora fenicalii sp. nov., CNT-569T (=DSM 108614T=CECT 9740T); Salinispora goodfellowii sp. nov., CNY-666T (=DSM 108616T=CECT 9738T); Salinispora mooreana sp. nov., CNT-150T (=DSM 45549T=CECT 9741T); Salinispora oceanensis sp. nov., CNT-138T (=DSM 45547T=CECT 9742T); and Salinispora vitiensis sp. nov., CNT-148T (=DSM 45548T=CECT 9743T).


Assuntos
Sedimentos Geológicos/microbiologia , Micromonosporaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
17.
Int J Syst Evol Microbiol ; 70(8): 4531-4536, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32614764

RESUMO

A Gram-staining-negative bacterium, designated 345S023T, was isolated from a sea water sample from the Indian Ocean. The results of 16S rRNA gene sequence analysis revealed that 345S023T represents a member of the genus Alteromonas, with closely related type strains Alteromonas fortis 1T (98.7 %), Alteromonas hispanica F-32T (98.6 %) and Alteromonas genovensis LMG 24078T (98.6 %). Up-to-date bacterial core gene set analysis revealed that 345S023T formed a phyletic lineage with Alteromonas australica H 17T. The case for 345S023T representing a novel species was supported by genomic results. Pairwise in silico DNA-DNA hybridization and average nucleotide identity values were much lower than the proposed and generally accepted species boundaries. Strain 345S023T contains ubiquinone-8 (Q-8) as the sole isoprenoid quinone, summed featured 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C18 : 1ω7c as the dominant cellular fatty acids (>10 %), and phosphatidylglycerol and phosphatidylethanolamine as the major polar lipids. The genome of strain 345S023T consisted of a 4.4 Mb chromosome with a DNA G+C content of 44.4 %. On the basis of these genomic, chemotaxonomic and phenotypic characteristics, we propose a novel species: Alteromonas profundi sp. nov. The type strain is 345S023T(=JCM 33893T=MCCC 1K04570T).


Assuntos
Alteromonas/classificação , Filogenia , Água do Mar/microbiologia , Alteromonas/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
18.
Int J Syst Evol Microbiol ; 70(8): 4569-4575, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32634089

RESUMO

The Gram-stain-negative, orange-pigmented, non-spore-forming, non-motile, strictly aerobic, rod-shaped bacterial strain, designated TP-CH-4T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. The optimal growth conditions were determined to be at pH 7-8, 25-30 °C and in the presence of 2 % (w/v) NaCl. The major respiratory quinone was MK-6. The polar lipid profile contained phosphatidylethanolamine, two unidentified aminolipids, two unidentified phospholipids and three unidentified polar lipids. The predominant cellular fatty acids were iso-C15 : 0 and summed feature 1 (composed of C13 : 03-OH and/or iso-C15 : 1H). Phylogenetic analysis of 16S rRNA gene sequences revealed that strain TP-CH-4T was a member of the family Flavobacteriaceae and formed a distinct lineage. Strain TP-CH-4T displayed highest sequence similarities to Pseudozobellia thermophila KMM 3531T (95.1 %) and Flagellimonas flava A11T (93.9 %). Genome sequencing revealed the strain TP-CH-4T has a genome size of 4.5 Mbp and a G+C content of 44.5 mol%. Collectively, based on phenotypic, chemotaxonomic, phylogenetic and genomic evidence, strain TP-CH-4T represents a novel species of a novel genus of the family Flavobacteriaceae, for which the name Pelagihabitans pacificus gen. nov., sp. nov. is proposed. The type strain of Pelagihabitans pacificus is TP-CH-4T (=CGMCC 1.17120T=KCTC 72434T).


Assuntos
Flavobacteriaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Oceano Pacífico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
19.
PLoS One ; 15(6): e0235235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32598345

RESUMO

Mobile Bay, the fourth largest estuary in the USA located in the northern Gulf of Mexico, is known for extreme hypoxia in the water column during dry season caused by NH4+-rich and anoxic submarine groundwater discharge (SGD). Nutrient dynamics in the coastal ecosystem point to potentially elevated microbial activities; however, little is known about microbial community composition and their functional roles in this area. In this study, we investigated microbial community composition, distribution, and metabolic prediction along the coastal hydrological compartment of Mobile Bay using 16S rRNA gene sequencing. We collected microbial samples from surface (river and bay water) and subsurface water (groundwater and coastal pore water from two SGD sites with peat and sandy lithology, respectively). Salinity was identified as the primary factor affecting the distribution of microbial communities across surface water samples, while DON and PO43- were the major predictor of community shift within subsurface water samples. Higher microbial diversity was found in coastal pore water in comparison to surface water samples. Gammaproteobacteria, Bacteroidia, and Oxyphotobacteria dominated the bacterial community. Among the archaea, methanogens were prevalent in the peat-dominated SGD site, while the sandy SGD site was characterized by a higher proportion of ammonia-oxidizing archaea. Cyanobium PCC-6307 and unclassified Thermodesulfovibrionia were identified as dominant taxa strongly associated with trends in environmental parameters in surface and subsurface samples, respectively. Microbial communities found in the groundwater and peat layer consisted of taxa known for denitrification and dissimilatory nitrate reduction to ammonium (DNRA). This finding suggested that microbial communities might also play a significant role in mediating nitrogen transformation in the SGD flow path and in affecting the chemical composition of SGD discharging to the water column. Given the ecological importance of microorganisms, further studies at higher taxonomic and functional resolution are needed to accurately predict chemical biotransformation processes along the coastal hydrological continuum, which influence water quality and environmental condition in Mobile Bay.


Assuntos
Monitoramento Ambiental/métodos , Água Subterrânea/análise , Água Subterrânea/microbiologia , Microbiota , Água do Mar/análise , Água do Mar/microbiologia , Golfo do México , Hidrologia , RNA Ribossômico 16S/análise , Movimentos da Água
20.
Nat Commun ; 11(1): 3108, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561737

RESUMO

In the Southern Ocean, large-scale phytoplankton blooms occur in open water and the sea-ice zone (SIZ). These blooms have a range of fates including physical advection, downward carbon export, or grazing. Here, we determine the magnitude, timing and spatial trends of the biogeochemical (export) and ecological (foodwebs) fates of phytoplankton, based on seven BGC-Argo floats spanning three years across the SIZ. We calculate loss terms using the production of chlorophyll-based on nitrate depletion-compared with measured chlorophyll. Export losses are estimated using conspicuous chlorophyll pulses at depth. By subtracting export losses, we calculate grazing-mediated losses. Herbivory accounts for ~90% of the annually-averaged losses (169 mg C m-2 d-1), and phytodetritus POC export comprises ~10%. Furthermore, export and grazing losses each exhibit distinctive seasonality captured by all floats spanning 60°S to 69°S. These similar trends reveal widespread patterns in phytoplankton fate throughout the Southern Ocean SIZ.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Cadeia Alimentar , Camada de Gelo/microbiologia , Fitoplâncton/fisiologia , Água do Mar/microbiologia , Algoritmos , Clorofila/análise , Clorofila/metabolismo , Conjuntos de Dados como Assunto , Monitorização de Parâmetros Ecológicos/instrumentação , Eutrofização , Herbivoria , Oceanos e Mares , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Estações do Ano , Análise Espaço-Temporal
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