scholarly journals Relationship of Bacterial Richness to Organic Degradation Rate and Sediment Age in Subseafloor Sediment

2016 ◽  
Vol 82 (16) ◽  
pp. 4994-4999 ◽  
Author(s):  
Emily A. Walsh ◽  
John B. Kirkpatrick ◽  
Robert Pockalny ◽  
Justine Sauvage ◽  
Arthur J. Spivack ◽  
...  
Keyword(s):  
Microbial Diversity ◽  
Electron Donor ◽  
Degradation Rate ◽  
Open Ocean ◽  
Sediment Depth ◽  
Organic Degradation ◽  
Terminal Electron Acceptor ◽  
Bacterial Richness ◽  
The Impact ◽  
Sediment Age

ABSTRACTSubseafloor sediment hosts a large, taxonomically rich, and metabolically diverse microbial ecosystem. However, the factors that control microbial diversity in subseafloor sediment have rarely been explored. Here, we show that bacterial richness varies with organic degradation rate and sediment age. At three open-ocean sites (in the Bering Sea and equatorial Pacific) and one continental margin site (Indian Ocean), richness decreases exponentially with increasing sediment depth. The rate of decrease in richness with increasing depth varies from site to site. The vertical succession of predominant terminal electron acceptors correlates with abundance-weighted community composition but does not drive the vertical decrease in richness. Vertical patterns of richness at the open-ocean sites closely match organic degradation rates; both properties are highest near the seafloor and decline together as sediment depth increases. This relationship suggests that (i) total catabolic activity and/or electron donor diversity exerts a primary influence on bacterial richness in marine sediment and (ii) many bacterial taxa that are poorly adapted for subseafloor sedimentary conditions are degraded in the geologically young sediment, where respiration rates are high. Richness consistently takes a few hundred thousand years to decline from near-seafloor values to much lower values in deep anoxic subseafloor sediment, regardless of sedimentation rate, predominant terminal electron acceptor, or oceanographic context.IMPORTANCESubseafloor sediment provides a wonderful opportunity to investigate the drivers of microbial diversity in communities that may have been isolated for millions of years. Our paper shows the impact ofin situconditions on bacterial community structure in subseafloor sediment. Specifically, it shows that bacterial richness in subseafloor sediment declines exponentially with sediment age, and in parallel with organic-fueled oxidation rate. This result suggests that subseafloor diversity ultimately depends on electron donor diversity and/or total community respiration. This work studied how and why biological richness changes over time in the extraordinary ecosystem of subseafloor sediment.

scholarly journals Effects of Psychotropics on the Microbiome in Patients With Depression and Anxiety: Considerations in a Naturalistic Clinical Setting

2020 ◽  
Author(s):  
Yoshihiro Tomizawa ◽  
Shunya Kurokawa ◽  
Daiki Ishii ◽  
Katsuma Miyaho ◽  
Chiharu Ishii ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Microbial Diversity ◽  
Depressive Disorders ◽  
Alpha Diversity ◽  
16S Rrna Gene Sequencing ◽  
Shannon Index ◽  
Rrna Gene ◽  
Depression And Anxiety ◽  
The Impact ◽  
Whole Tree

Abstract Background The antibacterial effects of psychotropics may be part of their pharmacological effects when treating depression. However, limited studies have focused on gut microbiota in relation to prescribed medication. Method We longitudinally investigated the relationship between patients’ prescribed medications and intestinal bacterial diversity in a naturalistic treatment course for patients with major depressive disorders and anxiety disorders. Patients were recruited and their stool was collected at 3 time points during their usual psychiatric treatments. Gut microbiota were analyzed using 16S rRNA gene sequencing. We examined the impact of psychotropics (i.e., antidepressants, anxiolytics, antipsychotics) on their gut microbial diversity and functions. Results We collected 246 stool samples from 40 patients. Despite no differences in microbial diversity between medication groups at the baseline, over the course of treatment, phylogenic diversity whole-tree diversity decreased in patients on antipsychotics compared with patients without (P = .027), and beta diversity followed this trend. Based on a fixed-effect model, antipsychotics predicted microbial diversity; the higher doses correlated with less diversity based on the Shannon index and phylogenic diversity whole tree (estimate = −0.00254, SE = 0.000595, P < .0001; estimate = −0.02644, SE = 0.00833, P = .002, respectively). Conclusion Antipsychotics may play a role in decreasing the alpha diversity of the gut microbiome among patients with depression and anxiety, and our results indicate a relationship with medication dosage. Future studies are warranted and should consider patients’ types and doses of antipsychotics in order to further elucidate the mechanisms of gut-brain interactions in psychiatric disorders.

scholarly journals Longitudinal sampling of external mucosae in farmed European seabass reveals the impact of water temperature on bacterial dynamics

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Daniela Rosado ◽  
Raquel Xavier ◽  
Jo Cable ◽  
Ricardo Severino ◽  
Pedro Tarroso ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Microbial Diversity ◽  
Water Temperature ◽  
Abiotic Factors ◽  
Seasonal Effect ◽  
Microbial Composition ◽  
Surrounding Water ◽  
European Seabass ◽  
And Function ◽  
The Impact

AbstractFish microbiota are intrinsically linked to health and fitness, but they are highly variable and influenced by both biotic and abiotic factors. Water temperature particularly limits bacterial adhesion and growth, impacting microbial diversity and bacterial infections on the skin and gills. Aquaculture is heavily affected by infectious diseases, especially in warmer months, and industry practices often promote stress and microbial dysbiosis, leading to an increased abundance of potentially pathogenic bacteria. In this regard, fish mucosa health is extremely important because it provides a primary barrier against pathogens. We used 16 rRNA V4 metataxonomics to characterize the skin and gill microbiota of the European seabass, Dicentrarchus labrax, and the surrounding water over 12 months, assessing the impact of water temperature on microbial diversity and function. We show that the microbiota of external mucosae are highly dynamic with consistent longitudinal trends in taxon diversity. Several potentially pathogenic genera (Aliivibrio, Photobacterium, Pseudomonas, and Vibrio) were highly abundant, showing complex interactions with other bacterial genera, some of which with recognized probiotic activity, and were also significantly impacted by changes in temperature. The surrounding water temperature influenced fish microbial composition, structure and function over time (days and months). Additionally, dysbiosis was more frequent in warmer months and during transitions between cold/warm months. We also detected a strong seasonal effect in the fish microbiota, which is likely to result from the compound action of several unmeasured environmental factors (e.g., pH, nutrient availability) beyond temperature. Our results highlight the importance of performing longitudinal studies to assess the impact of environmental factors on fish microbiotas.

Study on Chlorpyrifos Residues Degradation by Mutagenic Bacteria DX1 in Soil

2013 ◽  
Vol 726-731 ◽  
pp. 3992-3995
Author(s):  
Ming Fen Niu ◽  
Jian Wei ◽  
Chen Liang
Keyword(s):  
Degradation Rate ◽  
Ph Value ◽  
Orthogonal Experiment ◽  
Organic Fertilizer ◽  
Test Results ◽  
Soil Environment ◽  
Soil Fertilization ◽  
Spss Software ◽  
The Impact ◽  
Different Levels

In this study, it was carried out by designing PH, soil fertilization content, humidity and mutagenic bacteria DX1 inoculation concentration of orthogonal experiment to research chlorpyrifos degradation rate in the soil, which was affected by mutagenic bacteria DX1 in the soil environment. SPSS software was taken visualized analysis and variance analysis to evaluate the impact of different levels of the test results, to determine the factors which had significant impact on the experimental results. It showed that the best environmental factors of chlorpyrifos degradation rate in soil were the pH 7, organic fertilizer content 5mg/kg, the soil moisture 70%, inoculation volume 50ml/kg. The pH value and inoculation volume had a significant impact on chlorpyrifos degradation rate in soil; the soil humidity had little effect and the organic fertilizer content had almost no effect.

scholarly journals How marine emissions of bromoform impact the remote atmosphere

2019 ◽  
Vol 19 (17) ◽  
pp. 11089-11103 ◽  
Author(s):  
Yue Jia ◽  
Susann Tegtmeier ◽  
Elliot Atlas ◽  
Birgit Quack
Keyword(s):  
Dispersion Model ◽  
Hot Spot ◽  
Open Ocean ◽  
Advective Transport ◽  
Localized Source ◽  
Mixing Ratios ◽  
Low Wind Speed ◽  
Uniform Background ◽  
Lagrangian Dispersion ◽  
The Impact

Abstract. It is an open question how localized elevated emissions of bromoform (CHBr3) and other very short-lived halocarbons (VSLHs), found in coastal and upwelling regions, and low background emissions, typically found over the open ocean, impact the atmospheric VSLH distribution. In this study, we use the Lagrangian dispersion model FLEXPART to simulate atmospheric CHBr3 resulting from assumed uniform background emissions, and from elevated emissions consistent with those derived during three tropical cruise campaigns. The simulations demonstrate that the atmospheric CHBr3 distributions in the uniform background emissions scenario are highly variable with high mixing ratios appearing in regions of convergence or low wind speed. This relation holds on regional and global scales. The impact of localized elevated emissions on the atmospheric CHBr3 distribution varies significantly from campaign to campaign. The estimated impact depends on the strength of the emissions and the meteorological conditions. In the open waters of the western Pacific and Indian oceans, localized elevated emissions only slightly increase the background concentrations of atmospheric CHBr3, even when 1∘ wide source regions along the cruise tracks are assumed. Near the coast, elevated emissions, including hot spots up to 100 times larger than the uniform background emissions, can be strong enough to be distinguished from the atmospheric background. However, it is not necessarily the highest hot spot emission that produces the largest enhancement, since the tug-of-war between fast advective transport and local accumulation at the time of emission is also important. Our results demonstrate that transport variations in the atmosphere itself are sufficient to produce highly variable VSLH distributions, and elevated VSLHs in the atmosphere do not always reflect a strong localized source. Localized elevated emissions can be obliterated by the highly variable atmospheric background, even if they are orders of magnitude larger than the average open ocean emissions.

scholarly journals Plant Taxonomic Diversity Better Explains Soil Fungal and Bacterial Diversity than Functional Diversity in Restored Forest Ecosystems

Plants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 479 ◽  
Author(s):  
Hanif ◽  
Guo ◽  
Moniruzzaman ◽  
He ◽  
Yu ◽  
...  
Keyword(s):  
Species Richness ◽  
Microbial Diversity ◽  
Soil Properties ◽  
Bacterial Diversity ◽  
Functional Diversity ◽  
Forest Ecosystems ◽  
Taxonomic Diversity ◽  
Soil Microbial Diversity ◽  
Soil Microbial ◽  
Bacterial Richness

Plant attributes have direct and indirect effects on soil microbes via plant inputs and plant-mediated soil changes. However, whether plant taxonomic and functional diversities can explain the soil microbial diversity of restored forest ecosystems remains elusive. Here, we tested the linkage between plant attributes and soil microbial communities in four restored forests (Acacia species, Eucalyptus species, mixed coniferous species, mixed native species). The trait-based approaches were applied for plant properties and high-throughput Illumina sequencing was applied for fungal and bacterial diversity. The total number of soil microbial operational taxonomic units (OTUs) varied among the four forests. The highest richness of fungal OTUs was found in the Acacia forest. However, bacterial OTUs were highest in the Eucalyptus forest. Species richness was positively and significantly related to fungal and bacterial richness. Plant taxonomic diversity (species richness and species diversity) explained more of the soil microbial diversity than the functional diversity and soil properties. Prediction of fungal richness was better than that of bacterial richness. In addition, root traits explained more variation than the leaf traits. Overall, plant taxonomic diversity played a more important role than plant functional diversity and soil properties in shaping the soil microbial diversity of the four forests.

scholarly journals The Impact of Tides on the Bay of Biscay Dynamics

2020 ◽  
Vol 8 (8) ◽  
pp. 617
Author(s):  
John Karagiorgos ◽  
Vassilios Vervatis ◽  
Sarantis Sofianos
Keyword(s):  
Vertical Mixing ◽  
Ocean Model ◽  
Open Ocean ◽  
Small Scale ◽  
Bay Of Biscay ◽  
English Channel ◽  
Tidal Forcing ◽  
Freshwater Transport ◽  
One Year ◽  
The Impact

The impact of tides on the Bay of Biscay dynamics is investigated by means of an ocean model twin-experiment, consisted of two simulations with and without tidal forcing. The study is based on a high-resolution (1/36∘) regional configuration of NEMO (Nucleus for European Modelling of the Ocean) performing one-year simulations. The results highlight the imprint of tides on the thermohaline properties and circulation patterns in three distinct dynamical areas in the model domain: the abyssal plain, the Armorican shelf and the English Channel. When tides are activated, the bottom stress is increased in the shelf areas by about two orders of magnitude with respect to the open ocean, subsequently enhancing vertical mixing and weakening stratification in the bottom boundary layer. The most prominent feature reproduced only when tides are modelled, is the Ushant front near the entrance of the English Channel. Tides appear also to constrain the freshwater transport of rivers from the continental shelf to the open ocean. The spectral analysis revealed that the tidal forcing contributes to the SSH variance at high frequencies near the semidiurnal band and to the open ocean mesoscale and small-scale features in the presence of summer stratification pattern.

scholarly journals Bioactive Compounds from Marine-Derived Aspergillus, Penicillium, Talaromyces and Trichoderma Species

Marine Drugs ◽  
2018 ◽  
Vol 16 (11) ◽  
pp. 408 ◽  
Author(s):  
Rosario Nicoletti ◽  
Francesco Vinale
Keyword(s):  
Microbial Diversity ◽  
Bioactive Compounds ◽  
Scientific Community ◽  
Human Life ◽  
Trichoderma Species ◽  
Natural Sources ◽  
The Impact

The impact of bioactive compounds from natural sources on human life, particularly in pharmacology and biotechnology, has challenged the scientific community to explore new environmental contexts and the associated microbial diversity. [...]

scholarly journals The impact of feed efficiency selection on the ruminal, cecal, and fecal microbiomes of Angus steers from a commercial feedlot

2020 ◽  
Vol 98 (7) ◽  
Author(s):  
Christina B Welch ◽  
Jeferson M Lourenco ◽  
Dylan B Davis ◽  
Taylor R Krause ◽  
Mia N Carmichael ◽  
...  
Keyword(s):  
Feed Efficiency ◽  
Bacterial Population ◽  
Diversity Index ◽  
16S Rrna Gene Sequencing ◽  
Nutrient Utilization ◽  
Rrna Gene ◽  
Feedlot Steers ◽  
Taxonomic Profile ◽  
Bacterial Richness ◽  
The Impact

Abstract Feed is the greatest cost of animal production, so reducing it is critical to increase producer profits. In ruminants, the microbial population within the gastrointestinal tract (GIT) is critical to nutrient digestion and absorption in both the rumen and the hindgut. The objective of this study was to determine the bacterial taxonomic profile of the rumen, cecum, and feces of feedlot steers at slaughter in order to link feed efficiency and the GIT bacterial populations from these three locations. Twenty commercial Angus steers were selected and divided into two groups according to their residual feed intake (RFI) classification determined during the feedlot-finishing period: high-RFI (n = 10) and low-RFI (n = 10). After the ruminal, cecal, and fecal samples were collected at slaughter, DNA extraction and 16S rRNA gene sequencing were performed on them to determine their bacterial composition. One-way ANOVA was performed on the animal performance data, alpha diversities, and bacterial abundances using RFI classification as the fixed effect. Overall, the ruminal bacterial population was the most different in terms of taxonomic profile compared with the cecal and fecal populations as revealed by beta diversity analysis (P < 0.001). Moreover, bacterial richness (Chao1) was greatest (P = 0.01) in the rumen of the high-RFI group compared with the low-RFI group. In contrast, bacterial richness and diversity in the intestinal environment showed that Chao1 was greater (P = 0.01) in the cecum, and the Shannon diversity index was greater in both the cecum and feces of low-RFI compared with high-RFI steers (P = 0.01 and P < 0.001, respectively). Ruminococcaceae was more abundant in the low-RFI group in the cecum and feces (P = 0.01); fecal Bifidobacteriaceae was more abundant in high-RFI steers (P = 0.03). No correlations (P ≥ 0.13) between any ruminal bacterial family and RFI were detected; however, Ruminococcaceae, Mogibacteriaceae, Christensenellaceae, and BS11 were negatively correlated with RFI (P < 0.05) in the cecum and feces. Succinivibrionaceae in the cecum was positively correlated with RFI (P = 0.05), and fecal Bifidobacteriaceae was positively correlated with RFI (P = 0.03). Results collectively indicate that in addition to the ruminal bacteria, the lower gut bacterial population has a significant impact on feed efficiency and nutrient utilization in feedlot steers; therefore, the intestinal bacteria should also be considered when examining the basis of ruminant feed efficiency.

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