Microbial community structure in hadal sediments: high similarity along trench axes and strong changes along redox gradients

AbstractHadal trench sediments are hotspots of biogeochemical activity in the deep sea, but the biogeochemical and ecological factors that shape benthic hadal microbial communities remain unknown. Here, we sampled ten hadal sites from two trench regions with a vertical resolution of down to 1 cm. We sequenced 16S rRNA gene amplicons using universal and archaea-specific primer sets and compared the results to biogeochemical parameters. Despite bathymetric and depositional heterogeneity we found a high similarity of microbial communities within each of the two trench axes, while composition at the phylum level varied strongly with sediment depth in conjunction with the redox stratification into oxic, nitrogenous, and ferruginous zones. As a result, communities of a given sediment horizon were more similar to each other across a distance of hundreds of kilometers within each trench, than to those of adjacent horizons from the same sites separated only by centimeters. Total organic carbon content statistically only explained a small part of the variation within and between trenches, and did not explain the community differences observed between the hadal and adjacent shallower sites. Anaerobic taxa increased in abundance at the top of the ferruginous zone, seeded by organisms deposited at the sediment surface and surviving burial through the upper redox zones. While an influence of other potential factors such as geographic isolation, hydrostatic pressure, and non-steady state depositional regimes could not be discerned, redox stratification and diagenesis appear to be the main selective forces that structure community composition in hadal sediments.

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Advantage of Using Inosine at the 3′ Termini of 16S rRNA Gene Universal Primers for the Study of Microbial Diversity

Applied and Environmental Microbiology ◽

10.1128/aem.00849-06 ◽

2006 ◽

Vol 72 (11) ◽

pp. 6902-6906 ◽

Cited By ~ 61

Author(s):

Eitan Ben-Dov ◽

Orr H. Shapiro ◽

Nachshon Siboni ◽

Ariel Kushmaro

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Microbial Diversity ◽

Microbial Communities ◽

Environmental Samples ◽

Annealing Temperature ◽

Universal Primers ◽

Rrna Gene ◽

Bacterial Phyla ◽

Primer Sets

ABSTRACT To overcome the shortcomings of universal 16S rRNA gene primers 8F and 907R when studying the diversity of complex microbial communities, the 3′ termini of both primers were replaced with inosine. A comparison of the clone libraries derived using both primer sets showed seven bacterial phyla amplified by the altered primer set (8F-I/907R-I) whereas the original set amplified sequences belonging almost exclusively to Proteobacteria (95.8%). Sequences belonging to Firmicutes (42.6%) and Thermotogae (9.3%) were more abundant in a library obtained by using 8F-I/907R-I at a PCR annealing temperature of 54°C, while Proteobacteria sequences were more frequent (62.7%) in a library obtained at 50°C, somewhat resembling the result obtained using the original primer set. The increased diversity revealed by using primers 8F-I/907R-I confirms the usefulness of primers with inosine at the 3′ termini in studying the microbial diversity of environmental samples.

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Occurrence of Mycoplasma spp. in wild birds: phylogenetic analysis and potential factors affecting distribution

Scientific Reports ◽

10.1038/s41598-021-96577-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Anna Sawicka-Durkalec ◽

Olimpia Kursa ◽

Łukasz Bednarz ◽

Grzegorz Tomczyk

Keyword(s):

Phylogenetic Analysis ◽

Feeding Habits ◽

Bird Species ◽

Ecological Factors ◽

Wild Birds ◽

Rrna Gene ◽

Factors Affecting ◽

Pcr Products ◽

Commercial Poultry ◽

Potential Factors

AbstractDifferent Mycoplasma species have been reported in avian hosts. However, the majority of studies focus on one particular species of Mycoplasma or one host. In our research, we screened a total of 1141 wild birds representing 55 species, 26 families, and 15 orders for the presence of mycoplasmas by conventional PCR based on the 16S rRNA gene. Selected PCR products were sequenced to perform the phylogenetic analysis. All mycoplasma-positive samples were tested for M. gallisepticum and M. synoviae, which are considered the major pathogens of commercial poultry. We also verified the influence of ecological characteristics of the tested bird species including feeding habits, habitat types, and movement patterns. The presence of Mycoplasma spp. was confirmed in 498 birds of 29 species, but none of the tested birds were positive for M. gallisepticum or M. synoviae. We found possible associations between the presence of Mycoplasma spp. and all investigated ecological factors. The phylogenetic analysis showed a high variability of Mycoplasma spp.; however, some clustering of sequences was observed regarding particular bird species. We found that wild migratory waterfowl, particularly the white-fronted goose (Anser albifrons) and mallard (Anas platyrhynchos) could be reservoirs and vectors of mycoplasmas pathogenic to commercial waterfowl.

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Effects of Living Cover on the Soil Microbial Communities and Ecosystem Functions of Hazelnut Orchards

Frontiers in Plant Science ◽

10.3389/fpls.2021.652493 ◽

2021 ◽

Vol 12 ◽

Author(s):

Wenxu Ma ◽

Zhen Yang ◽

Sihao Hou ◽

Qinghua Ma ◽

Lisong Liang ◽

...

Keyword(s):

Soil Properties ◽

Microbial Communities ◽

Soil Depth ◽

Soil Microbial Communities ◽

Ecosystem Functions ◽

Available Phosphorus ◽

Rrna Gene ◽

Organic Carbon Content ◽

Community Structures ◽

Management Measure

Living cover is an important management measure for orchards in China, and has certain influences on soil properties, microorganisms, and the micro-ecological environment. However, there are few studies on the effects of living cover on the soil changes in hazelnut orchards. In this study, we compared the soils of living cover treatments with Vulpia myuros and the soils of no cover treatments, and analyzed the observed changes in soil properties, microorganisms, and microbial functions by using high-throughput ITS rDNA and 16S rRNA gene Illumina sequencing. The results demonstrated that the total organic carbon content in the 20–40 cm deep soils under the living cover treatments increased by 32.87 and 14.82% in May and July, respectively, compared with those under the no cover treatments. The living cover treatment with V. myuros also significantly increased the contents of total phosphorus (TP), total nitrogen (TN), available phosphorus (AP), and available potassium (AK) in the soil samples. Moreover, the influence of seasons was not as significant as that of soil depth. The living cover treatment also significantly improved the soil enzyme activity levels. The results demonstrated that Ascomycota, Mortierellomycota and Basidiomycota were the dominant fungal phyla in all samples, while Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes, and Chloroflexi were the dominant bacterial phyla, but the different treatments impacted the compositions of fungal and bacterial communities. Principal component analysis (PCA) showed that living cover with V. myuros significantly changed the soil fungal community structures whereas the bacterial community structures may be more sensitive to seasonal changes. At the microbial functional level, the living cover treatment increased the fungal operational taxonomic units (OTUs) of symbiotrophs and decreased that of pathotrophs. According to this study, we believe that the application of a living cover with V. myuros has a favorable regulating influence on soil properties, microbial communities and microbial function. This treatment can also reduce the use of herbicides, reduce the cost of orchard management, and store more carbon underground to achieve sustainable intensification of production in hazelnut orchards, so it can be considered as a management measure for hazelnut orchards.

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Comparison of Two 16S rRNA Primers (V3–V4 and V4–V5) for Studies of Arctic Microbial Communities

Frontiers in Microbiology ◽

10.3389/fmicb.2021.637526 ◽

2021 ◽

Vol 12 ◽

Author(s):

Eduard Fadeev ◽

Magda G. Cardozo-Mino ◽

Josephine Z. Rapp ◽

Christina Bienhold ◽

Ian Salter ◽

...

Keyword(s):

Microbial Community ◽

16S Rrna ◽

Microbial Communities ◽

Arctic Ocean ◽

The Arctic ◽

Rrna Gene ◽

Marine Habitats ◽

The Arctic Ocean ◽

Primer Sets ◽

Extreme Seasonality

Microbial communities of the Arctic Ocean are poorly characterized in comparison to other aquatic environments as to their horizontal, vertical, and temporal turnover. Yet, recent studies showed that the Arctic marine ecosystem harbors unique microbial community members that are adapted to harsh environmental conditions, such as near-freezing temperatures and extreme seasonality. The gene for the small ribosomal subunit (16S rRNA) is commonly used to study the taxonomic composition of microbial communities in their natural environment. Several primer sets for this marker gene have been extensively tested across various sample sets, but these typically originated from low-latitude environments. An explicit evaluation of primer-set performances in representing the microbial communities of the Arctic Ocean is currently lacking. To select a suitable primer set for studying microbiomes of various Arctic marine habitats (sea ice, surface water, marine snow, deep ocean basin, and deep-sea sediment), we have conducted a performance comparison between two widely used primer sets, targeting different hypervariable regions of the 16S rRNA gene (V3–V4 and V4–V5). We observed that both primer sets were highly similar in representing the total microbial community composition down to genus rank, which was also confirmed independently by subgroup-specific catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH) counts. Each primer set revealed higher internal diversity within certain bacterial taxonomic groups (e.g., the class Bacteroidia by V3–V4, and the phylum Planctomycetes by V4–V5). However, the V4–V5 primer set provides concurrent coverage of the archaeal domain, a relevant component comprising 10–20% of the community in Arctic deep waters and the sediment. Although both primer sets perform similarly, we suggest the use of the V4–V5 primer set for the integration of both bacterial and archaeal community dynamics in the Arctic marine environment.

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A Comparative Study on the Microbial Communities of Rhynchophorus ferrugineus (Red Palm Weevil)-Infected and Healthy Palm Trees

Arabian Journal for Science and Engineering ◽

10.1007/s13369-021-05979-9 ◽

2021 ◽

Author(s):

N. Alshammari ◽

Meshari Alazmi ◽

Naimah A. Alanazi ◽

Abdel Moneim E. Sulieman ◽

Vajid N. Veettil ◽

...

Keyword(s):

Microbial Communities ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Rhynchophorus Ferrugineus ◽

Tree Trunk ◽

Red Palm Weevil ◽

Healthy Tree ◽

Palm Trees ◽

Infected Tree ◽

Palm Weevil

AbstractSeveral studies have investigated palm trees’ microbiota infected with red palm weevil (RPW) (Rhynchophorus ferrugineus), the major pest of palm trees. This study compared the microbial communities of infected and uninfected palm trees in the Hail region, Northern Saudi Arabia, determined by high-throughput 16S rRNA gene sequencing by Illumina MiSeq. The results indicated that taxonomic diversity variation was higher for infected tree trunk than the healthy tree trunk. Soil samples from the vicinity of healthy and infected trees did not have a significant variation in bacterial diversity. Myxococcota, Acidobacteriota, and Firmicutes were the dominant phyla in RPW-infected tree trunk, and Pseudomonadaceae was the most prominent family. This study is the first report on the characterization of RPW-infected and healthy palm trees’ microbiome.

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Structure of Microbial Communities When Complementary Effluents Are Anaerobically Digested

Applied Sciences ◽

10.3390/app11031293 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1293

Author(s):

Ana Eusébio ◽

André Neves ◽

Isabel Paula Marques

Keyword(s):

Anaerobic Digestion ◽

Microbial Communities ◽

Volatile Fatty Acids ◽

Olive Mill Wastewater ◽

Organic Load ◽

Rrna Gene ◽

Bacterial Populations ◽

Next Generation Sequencing Ngs ◽

Generation Sequencing ◽

Olive Mill

Olive oil and pig productions are important industries in Portugal that generate large volumes of wastewater with high organic load and toxicity, raising environmental concerns. The principal objective of this study is to energetically valorize these organic effluents—piggery effluent and olive mill wastewater—through the anaerobic digestion to the biogas/methane production, by means of the effluent complementarity concept. Several mixtures of piggery effluent were tested, with an increasing percentage of olive mill wastewater. The best performance was obtained for samples of piggery effluent alone and in admixture with 30% of OMW, which provided the same volume of biogas (0.8 L, 70% CH4), 63/75% COD removal, and 434/489 L CH4/kg SVin, respectively. The validation of the process was assessed by molecular evaluation through Next Generation Sequencing (NGS) of the 16S rRNA gene. The structure of the microbial communities for both samples, throughout the anaerobic process, was characterized by the predominance of bacterial populations belonging to the phylum Firmicutes, mainly Clostridiales, with Bacteroidetes being the subdominant populations. Archaea populations belonging to the genus Methanosarcina became predominant throughout anaerobic digestion, confirming the formation of methane mainly from acetate, in line with the greatest removal of volatile fatty acids (VFAs) in these samples.

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Dissimilarity of microbial diversity of pond water, shrimp intestine and sediment in Aquamimicry system

AMB Express ◽

10.1186/s13568-020-01119-y ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Shenzheng Zeng ◽

Sukontorn Khoruamkid ◽

Warinphorn Kongpakdee ◽

Dongdong Wei ◽

Lingfei Yu ◽

...

Keyword(s):

Microbial Communities ◽

Well Being ◽

Pacific White Shrimp ◽

Shrimp Farming ◽

Rrna Gene ◽

Microbial Composition ◽

Shrimp Culture ◽

Water And Sediment ◽

Surrounding Environment ◽

Shrimp Production

Abstract The Pacific white shrimp, with the largest production in shrimp industry, has suffered from multiple severe viral and bacterial diseases, which calls for a more reliable and environmentally friendly system to promote shrimp culture. The “Aquamimicry system”, mimicking the nature of aquatic ecosystems for the well-being of aquatic animals, has effectively increased shrimp production and been adapted in many countries. However, the microbial communities in the shrimp intestine and surrounding environment that act as an essential component in Aquamimicry remain largely unknown. In this study, the microbial composition and diversity alteration in shrimp intestine, surrounding water and sediment at different culture stages were investigated by high throughput sequencing of 16S rRNA gene, obtaining 13,562 operational taxonomic units (OTUs). Results showed that the microbial communities in shrimp intestine and surrounding environment were significantly distinct from each other, and 23 distinguished taxa for each habitat were further characterized. The microbial communities differed significantly at different culture stages, confirmed by a great number of OTUs dramatically altered during the culture period. A small part of these altered OTUs were shared between shrimp intestine and surrounding environment, suggesting that the microbial alteration of intestine was not consistent with that of water and sediment. Regarding the high production of Aquamimicry farm used as a case in this study, the dissimilarity between intestinal and surrounding microbiota might be considered as a potential indicator for healthy status of shrimp farming, which provided hints on the appropriate culture practices to improve shrimp production.

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Microbial drivers of methane emissions from unrestored industrial salt ponds

The ISME Journal ◽

10.1038/s41396-021-01067-w ◽

2021 ◽

Author(s):

Jinglie Zhou ◽

Susanna M. Theroux ◽

Clifton P. Bueno de Mesquita ◽

Wyatt H. Hartman ◽

Ye Tian ◽

...

Keyword(s):

Microbial Communities ◽

Methane Flux ◽

Methane Emissions ◽

Metagenomic Data ◽

Rrna Gene ◽

Salt Ponds ◽

Salt Pond ◽

Reference Wetlands ◽

Reference Wetland ◽

The Impact

AbstractWetlands are important carbon (C) sinks, yet many have been destroyed and converted to other uses over the past few centuries, including industrial salt making. A renewed focus on wetland ecosystem services (e.g., flood control, and habitat) has resulted in numerous restoration efforts whose effect on microbial communities is largely unexplored. We investigated the impact of restoration on microbial community composition, metabolic functional potential, and methane flux by analyzing sediment cores from two unrestored former industrial salt ponds, a restored former industrial salt pond, and a reference wetland. We observed elevated methane emissions from unrestored salt ponds compared to the restored and reference wetlands, which was positively correlated with salinity and sulfate across all samples. 16S rRNA gene amplicon and shotgun metagenomic data revealed that the restored salt pond harbored communities more phylogenetically and functionally similar to the reference wetland than to unrestored ponds. Archaeal methanogenesis genes were positively correlated with methane flux, as were genes encoding enzymes for bacterial methylphosphonate degradation, suggesting methane is generated both from bacterial methylphosphonate degradation and archaeal methanogenesis in these sites. These observations demonstrate that restoration effectively converted industrial salt pond microbial communities back to compositions more similar to reference wetlands and lowered salinities, sulfate concentrations, and methane emissions.

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Collection of a Bacterial Community Reconstructed from Marine Metagenomes Derived from Jinhae Bay, South Korea

Data ◽

10.3390/data6050044 ◽

2021 ◽

Vol 6 (5) ◽

pp. 44

Author(s):

Jae-Hyun Lim ◽

Il-Nam Kim

Keyword(s):

Microbial Community ◽

South Korea ◽

Microbial Communities ◽

Marine Bacteria ◽

Sampling Site ◽

Community Change ◽

Rrna Gene ◽

Water Column Stratification ◽

Metagenomics Data ◽

Jinhae Bay

Marine bacteria are known to play significant roles in marine biogeochemical cycles regarding the decomposition of organic matter. Despite the increasing attention paid to the study of marine bacteria, research has been too limited to fully elucidate the complex interaction between marine bacterial communities and environmental variables. Jinhae Bay, the study area in this work, is the most anthropogenically eutrophied coastal bay in South Korea, and while its physical and biogeochemical characteristics are well described, less is known about the associated changes in microbial communities. In the present study, we reconstructed a metagenomics data based on the 16S rRNA gene to investigate temporal and vertical changes in microbial communities at three depths (surface, middle, and bottom) during a seven-month period from June to December 2016 at one sampling site (J1) in Jinhae Bay. Of all the bacterial data, Proteobacteria, Bacteroidetes, and Cyanobacteria were predominant from June to November, whereas Firmicutes were predominant in December, especially at the middle and bottom depths. These results show that the composition of the microbial community is strongly associated with temporal changes. Furthermore, the community compositions were markedly different between the surface, middle, and bottom depths in summer, when water column stratification and bottom water hypoxia (low dissolved oxygen level) were strongly developed. Metagenomics data contribute to improving our understanding of important relationships between environmental characteristics and microbial community change in eutrophication-induced and deoxygenated coastal areas.

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Impact of Substratum Surface on Microbial Community Structure and Treatment Performance in Biological Aerated Filters

Applied and Environmental Microbiology ◽

10.1128/aem.03001-13 ◽

2013 ◽

Vol 80 (1) ◽

pp. 177-183 ◽

Cited By ~ 10

Author(s):

Lavane Kim ◽

Eulyn Pagaling ◽

Yi Y. Zuo ◽

Tao Yan

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Bacterial Species ◽

Community Analysis ◽

Microbial Community Analysis ◽

Rrna Gene ◽

Content Type ◽

Property Change ◽

And Control ◽

Start Ups

ABSTRACTThe impact of substratum surface property change on biofilm community structure was investigated using laboratory biological aerated filter (BAF) reactors and molecular microbial community analysis. Two substratum surfaces that differed in surface properties were created via surface coating and used to develop biofilms in test (modified surface) and control (original surface) BAF reactors. Microbial community analysis by 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis (DGGE) showed that the surface property change consistently resulted in distinct profiles of microbial populations during replicate reactor start-ups. Pyrosequencing of the bar-coded 16S rRNA gene amplicons surveyed more than 90% of the microbial diversity in the microbial communities and identified 72 unique bacterial species within 19 bacterial orders. Among the 19 orders of bacteria detected,BurkholderialesandRhodocyclalesof theBetaproteobacteriaclass were numerically dominant and accounted for 90.5 to 97.4% of the sequence reads, and their relative abundances in the test and control BAF reactors were different in consistent patterns during the two reactor start-ups. Three of the five dominant bacterial species also showed consistent relative abundance changes between the test and control BAF reactors. The different biofilm microbial communities led to different treatment efficiencies, with consistently higher total organic carbon (TOC) removal in the test reactor than in the control reactor. Further understanding of how surface properties affect biofilm microbial communities and functional performance would enable the rational design of new generations of substrata for the improvement of biofilm-based biological treatment processes.

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