RESPONSE OF HETEROTROPHIC MICROBIAL COMMUNITIES TO AN ENVIRONMENTAL GRADIENT IN THE FLOODPLAIN OF MAPIRE RIVER, VENEZUELA

Abstract Soil physico-chemical characteristics of floodplains, particularly hydrology, influence microbiological activity. As such, each river floodplain system has a unique physico-chemical dynamic that in turn supports the microbial community. The Mapire River floodplain is a complex system in which seasonal flood pulses cause changes in the soil physico-chemical variables. We examined how these temporal and spatial differences are associated with the microbiological activity along a seasonally flooded gradient at the mouth of the Mapire River (Lower Orinoco, Venezuela). Soil samples were collected during three different seasons by a systematic sampling at 4 points of the gradient, defined by the intensity of flooding. The physico-chemical parameters of the soil were determined and related by the density and physiological profile of the microbial community through multivariate permutation analysis and gradient analysis. The results indicate that there is a spatial gradient determined by soil clay content and a temporal gradient influenced by moisture and total organic carbon. Significant differences were found among soil zones and seasons, with the interaction of both factors also significant. It was observed that microbial activity is decisive in phosphorus dynamics, even during flooding. It is concluded that amid the complex interactions between biotic and abiotic factors, microbial communities are able to respond to changes in the physico-chemical soil environment and maintain their activity throughout the hydroperiod.

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Thermodynamically Favorable Reactions Shape the Archaeal Community Affecting Bacterial Community Assembly in Oil Reservoirs

10.21203/rs.3.rs-41490/v1 ◽

2020 ◽

Author(s):

Xiao-Lei Wu ◽

Jie-Yu Zhao ◽

Bing Hu ◽

Yan Li ◽

Yue-Qin Tang ◽

...

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Community Assembly ◽

Abiotic Factors ◽

Oil Reservoirs ◽

16S Rrna Genes ◽

Rrna Genes ◽

Distribution Analysis ◽

The Core ◽

Archaeal Communities

Abstract Background: Microbial communities exist everywhere on the earth, and play essential roles in biogeochemical cycling in all ecosystems. Understanding microbial community assembly mechanisms could improve our ability to manage microbial ecosystems for industrial, pharmaceutical, and agricultural applications. Previous studies have shown that microbial communities are shaped by deterministic or stochastic processes, but how these two processes influence the microbial community together is rarely investigated, especially in deep terrestrial ecology. Methods: Here, the microbial compositions in the production waters collected from water injection wells and oil production wells across eight oil reservoirs throughout northern China were determined using high-throughput 454 pyrosequencing of 16S rRNA genes, and analyzed by proportional distribution analysis and null model analysis. Results: In the study, a ‘core’ microbiota consisting of three bacterial genera and eight archaeal genera were found to be existent in all production water samples. Canonical correlation analysis reflected that these core archaea were significantly influenced by the abiotic factors of temperature and reservoir depth, while the core bacteria were affected by the combined impact of the core archaea and environmental factors. Considering that two of the core archaeal genera, acetoclastic methanogens and hydrogenotrophic methanogens, were enriched in low- and high-temperature oil reservoirs, respectively, it was proposed that the archaeal communities in oil reservoirs were characterized by thermodynamic constraints. Conclusions: Together, our study indicates that microbial community structures in wells of oil reservoirs are originally determined by the thermodynamic conditions, through which the core archaeal communities are shaped directly followed by the deterministic recruiting of core bacterial genera, and then the stochastically selection of some other microbial members from local environments.

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A peek in the micro-sized world: a review of design principles, engineering tools, and applications of engineered microbial community

Biochemical Society Transactions ◽

10.1042/bst20190172 ◽

2020 ◽

Vol 48 (2) ◽

pp. 399-409

Author(s):

Baizhen Gao ◽

Rushant Sabnis ◽

Tommaso Costantini ◽

Robert Jinkerson ◽

Qing Sun

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Environmental Remediation ◽

Real Life ◽

Design Principles ◽

Microbial Interactions ◽

Potential Applications ◽

New Gene ◽

Global Biogeochemical Cycles ◽

Synthetic Microbial Communities

Microbial communities drive diverse processes that impact nearly everything on this planet, from global biogeochemical cycles to human health. Harnessing the power of these microorganisms could provide solutions to many of the challenges that face society. However, naturally occurring microbial communities are not optimized for anthropogenic use. An emerging area of research is focusing on engineering synthetic microbial communities to carry out predefined functions. Microbial community engineers are applying design principles like top-down and bottom-up approaches to create synthetic microbial communities having a myriad of real-life applications in health care, disease prevention, and environmental remediation. Multiple genetic engineering tools and delivery approaches can be used to ‘knock-in' new gene functions into microbial communities. A systematic study of the microbial interactions, community assembling principles, and engineering tools are necessary for us to understand the microbial community and to better utilize them. Continued analysis and effort are required to further the current and potential applications of synthetic microbial communities.

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CaptureSeq: Hybridization-Based Enrichment of cpn60 Gene Fragments Reveals the Community Structures of Synthetic and Natural Microbial Ecosystems

Microorganisms ◽

10.3390/microorganisms9040816 ◽

2021 ◽

Vol 9 (4) ◽

pp. 816

Author(s):

Matthew G. Links ◽

Tim J. Dumonceaux ◽

E. Luke McCarthy ◽

Sean M. Hemmingsen ◽

Edward Topp ◽

...

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Dna Sequences ◽

Pcr Amplification ◽

Shotgun Sequencing ◽

Natural Ecosystems ◽

Gene Markers ◽

Microbial Profile ◽

Microbial Ecosystems ◽

Pcr Targeting

Background. The molecular profiling of complex microbial communities has become the basis for examining the relationship between the microbiome composition, structure and metabolic functions of those communities. Microbial community structure can be partially assessed with “universal” PCR targeting taxonomic or functional gene markers. Increasingly, shotgun metagenomic DNA sequencing is providing more quantitative insight into microbiomes. However, both amplicon-based and shotgun sequencing approaches have shortcomings that limit the ability to study microbiome dynamics. Methods. We present a novel, amplicon-free, hybridization-based method (CaptureSeq) for profiling complex microbial communities using probes based on the chaperonin-60 gene. Molecular profiles of a commercially available synthetic microbial community standard were compared using CaptureSeq, whole metagenome sequencing, and 16S universal target amplification. Profiles were also generated for natural ecosystems including antibiotic-amended soils, manure storage tanks, and an agricultural reservoir. Results. The CaptureSeq method generated a microbial profile that encompassed all of the bacteria and eukaryotes in the panel with greater reproducibility and more accurate representation of high G/C content microorganisms compared to 16S amplification. In the natural ecosystems, CaptureSeq provided a much greater depth of coverage and sensitivity of detection compared to shotgun sequencing without prior selection. The resulting community profiles provided quantitatively reliable information about all three domains of life (Bacteria, Archaea, and Eukarya) in the different ecosystems. The applications of CaptureSeq will facilitate accurate studies of host-microbiome interactions for environmental, crop, animal and human health. Conclusions: cpn60-based hybridization enriched for taxonomically informative DNA sequences from complex mixtures. In synthetic and natural microbial ecosystems, CaptureSeq provided sequences from prokaryotes and eukaryotes simultaneously, with quantitatively reliable read abundances. CaptureSeq provides an alternative to PCR amplification of taxonomic markers with deep community coverage while minimizing amplification biases.

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Pollutant-Removing Biofilter Strains Associated with High Ammonia and Hydrogen Sulfide Removal Rate in a Livestock Wastewater Treatment Facility

Sustainability ◽

10.3390/su13137358 ◽

2021 ◽

Vol 13 (13) ◽

pp. 7358

Author(s):

Dong-Hyun Kim ◽

Hyun-Sik Yun ◽

Young-Saeng Kim ◽

Jong-Guk Kim

Keyword(s):

Wastewater Treatment ◽

Hydrogen Sulfide ◽

Microbial Community ◽

Microbial Communities ◽

Illumina Miseq ◽

Illumina Miseq Sequencing ◽

Miseq Sequencing ◽

Treatment Facility ◽

Livestock Wastewater ◽

Wastewater Treatment Facility

This study analyzed the microbial community metagenomically to determine the cause of the functionality of a livestock wastewater treatment facility that can effectively remove pollutants, such as ammonia and hydrogen sulfide. Illumina MiSeq sequencing was used in analyzing the composition and structure of the microbial community, and the 16S rRNA gene was used. Through Illumina MiSeq sequencing, information such as diversity indicators as well as the composition and structure of microbial communities present in the livestock wastewater treatment facility were obtained, and differences between microbial communities present in the investigated samples were compared. The number of reads, operational taxonomic units, and species richness were lower in influent sample (NLF), where the wastewater enters, than in effluent sample (NL), in which treated wastewater is found. This difference was greater in June 2019 than in January 2020, and the removal rates of ammonia (86.93%) and hydrogen sulfide (99.72%) were also higher in June 2019. In both areas, the community composition was similar in January 2020, whereas the influent sample (NLF) and effluent sample (NL) areas in June 2019 were dominated by Proteobacteria (76.23%) and Firmicutes (67.13%), respectively. Oleiphilaceae (40.89%) and Thioalkalibacteraceae (12.91%), which are related to ammonia and hydrogen sulfide removal, respectively, were identified in influent sample (NLF) in June 2019. They were more abundant in June 2019 than in January 2020. Therefore, the functionality of the livestock wastewater treatment facility was affected by characteristics, including the composition of the microbial community. Compared to Illumina MiSeq sequencing, fewer species were isolated and identified in both areas using culture-based methods, suggesting Illumina MiSeq sequencing as a powerful tool to determine the relevance of microbial communities for pollutant removal.

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Comparison of Drivers of Soil Microbial Communities Developed in Karst Ecosystems with Shallow and Deep Soil Depths

Agronomy ◽

10.3390/agronomy11010173 ◽

2021 ◽

Vol 11 (1) ◽

pp. 173

Author(s):

Huiling Guan ◽

Jiangwen Fan ◽

Haiyan Zhang ◽

Warwick Harris

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Soil Depth ◽

Phospholipid Fatty Acid ◽

Soil Microbial Communities ◽

Deep Soil ◽

Soil System ◽

Soil Microbial ◽

Total Soil ◽

Karst Ecosystems

Soil erosion is prevalent in karst areas, but few studies have compared the differences in the drivers for soil microbial communities among karst ecosystems with different soil depths, and most studies have focused on the local scale. To fill this research gap, we investigated the upper 20 cm soil layers of 10 shallow–soil depth (shallow–SDC, total soil depth less than 100 cm) and 11 deep–soil depth communities (deep–SDC, total soil depth more than 100 cm), covering a broad range of vegetation types, soils, and climates. The microbial community characteristics of both the shallow–SDC and deep–SDC soils were tested by phospholipid fatty acid (PLFAs) analysis, and the key drivers of the microbial communities were illustrated by forward selection and variance partitioning analysis. Our findings demonstrated that more abundant soil nutrients supported higher fungal PLFA in shallow–SDC than in deep–SDC (p < 0.05). Furthermore, stronger correlation between the microbial community and the plant–soil system was found in shallow–SDC: the pure plant effect explained the 43.2% of variance in microbial biomass and 57.8% of the variance in the ratio of Gram–positive bacteria to Gram–negative bacteria (G+/G−), and the ratio of fungi to total bacteria (F/B); the pure soil effect accounted for 68.6% variance in the microbial diversity. The ratio of microbial PLFA cyclopropyl to precursors (Cy/Pr) and the ratio of saturated PLFA to monounsaturated PLFA (S/M) as indicators of microbial stress were controlled by pH, but high pH was not conducive to microorganisms in this area. Meanwhile, Cy/Pr in all communities was >0.1, indicating that microorganisms were under environmental stress. Therefore, the further ecological restoration of degraded karst communities is needed to improve their microbial communities.

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Environmental parameters and microbial community profiles as indication towards microbial activities and diversity in aquaponic system compartments

BMC Microbiology ◽

10.1186/s12866-020-02075-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Zala Schmautz ◽

Carlos A. Espinal ◽

Andrea M. Bohny ◽

Fabio Rezzonico ◽

Ranka Junge ◽

...

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Profile Analysis ◽

Operation Mode ◽

Environmental Parameters ◽

Plant Production ◽

Microbial Activities ◽

Anaerobic Processes ◽

Abiotic Parameters ◽

Aerobic And Anaerobic

Abstract Background An aquaponic system couples cultivation of plants and fish in the same aqueous medium. The system consists of interconnected compartments for fish rearing and plant production, as well as for water filtration, with all compartments hosting diverse microbial communities, which interact within the system. Due to the design, function and operation mode of the individual compartments, each of them exhibits unique biotic and abiotic conditions. Elucidating how these conditions shape microbial communities is useful in understanding how these compartments may affect the quality of the water, in which plants and fish are cultured. Results We investigated the possible relationships between microbial communities from biofilms and water quality parameters in different compartments of the aquaponic system. Biofilm samples were analyzed by total community profiling for bacterial and archaeal communities. The results implied that the oxygen levels could largely explain the main differences in abiotic parameters and microbial communities in each compartment of the system. Aerobic system compartments are highly biodiverse and work mostly as a nitrifying biofilter, whereas biofilms in the anaerobic compartments contain a less diverse community. Finally, the part of the system connecting the aerobic and anaerobic processes showed common conditions where both aerobic and anaerobic processes were observed. Conclusion Different predicted microbial activities for each compartment were found to be supported by the abiotic parameters, of which the oxygen saturation, total organic carbon and total nitrogen differentiated clearly between samples from the main aerobic loop and the anaerobic compartments. The latter was also confirmed using microbial community profile analysis.

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Habitat Elevation Shapes Microbial Community Composition and Alter the Metabolic Functions in Wild Sable (Martes zibellina) Guts

Animals ◽

10.3390/ani11030865 ◽

2021 ◽

Vol 11 (3) ◽

pp. 865

Author(s):

Lantian Su ◽

Xinxin Liu ◽

Guangyao Jin ◽

Yue Ma ◽

Haoxin Tan ◽

...

Keyword(s):

Microbial Community ◽

Environmental Factors ◽

Microbial Communities ◽

Community Composition ◽

16S Rrna Genes ◽

Rrna Genes ◽

Functional Genes ◽

Martes Zibellina ◽

Clear Cutting ◽

Metabolic Functions

In recent decades, wild sable (Carnivora Mustelidae Martes zibellina) habitats, which are often natural forests, have been squeezed by anthropogenic disturbances such as clear-cutting, tilling and grazing. Sables tend to live in sloped areas with relatively harsh conditions. Here, we determine effects of environmental factors on wild sable gut microbial communities between high and low altitude habitats using Illumina Miseq sequencing of bacterial 16S rRNA genes. Our results showed that despite wild sable gut microbial community diversity being resilient to many environmental factors, community composition was sensitive to altitude. Wild sable gut microbial communities were dominated by Firmicutes (relative abundance 38.23%), followed by Actinobacteria (30.29%), and Proteobacteria (28.15%). Altitude was negatively correlated with the abundance of Firmicutes, suggesting sable likely consume more vegetarian food in lower habitats where plant diversity, temperature and vegetation coverage were greater. In addition, our functional genes prediction and qPCR results demonstrated that energy/fat processing microorganisms and functional genes are enriched with increasing altitude, which likely enhanced metabolic functions and supported wild sables to survive in elevated habitats. Overall, our results improve the knowledge of the ecological impact of habitat change, providing insights into wild animal protection at the mountain area with hash climate conditions.

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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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Effects of Community Versus Single Strain Inoculants on the Biocontrol of Salmonella and Microbial Community Dynamics in Alfalfa Sprouts†

Journal of Food Protection ◽

10.4315/0362-028x-68.1.40 ◽

2005 ◽

Vol 68 (1) ◽

pp. 40-48 ◽

Cited By ~ 40

Author(s):

ANABELLE MATOS ◽

JAY L. GARLAND

Keyword(s):

Microbial Community ◽

Microbial Communities ◽

Community Dynamics ◽

Community Level ◽

Microbial Consortia ◽

Single Strain ◽

Acridine Orange Staining ◽

Physiological Profiles ◽

Alfalfa Sprouts ◽

Alfalfa Seeds

Potential biological control inoculants, Pseudomonas fluorescens 2-79 and microbial communities derived from market sprouts or laboratory-grown alfalfa sprouts, were introduced into alfalfa seeds with and without a Salmonella inoculum. We examined their ability to inhibit the growth of this foodborne pathogen and assess the relative effects of the inoculants on the alfalfa microbial community structure and function. Alfalfa seeds contaminated with a Salmonella cocktail were soaked for 2 h in bacterial suspensions from each inoculant tested. Inoculated alfalfa seeds were grown for 7 days and sampled during days 1, 3, and 7. At each sampling, alfalfa sprouts were sonicated for 7 min to recover microflora from the surface, and the resulting suspensions were diluted and plated on selective and nonselective media. Total bacterial counts were obtained using acridine orange staining, and the percentage culturability was calculated. Phenotypic potential of sprout-associated microbial communities inoculated with biocontrol treatments was assessed using community-level physiological profiles based on patterns of use of 95 separate carbon sources in Biolog plates. Community-level physiological profiles were also determined using oxygen-sensitive fluorophore in BD microtiter plates to examine functional patterns in these communities. No significant differences in total and mesophilic aerobe microbial cell density or microbial richness resulting from the introduction of inoculants on alfalfa seeds with and without Salmonella were observed. P. fluorescens 2-79 exhibited the greatest reduction in the growth of Salmonella early during alfalfa growth (4.22 log at day 1), while the market sprout inoculum had the reverse effect, resulting in a maximum log reduction (5.48) of Salmonella on day 7. Community-level physiological profiles analyses revealed that market sprout communities peaked higher and faster compared with the other inoculants tested. These results suggest that different modes of actions of single versus microbial consortia biocontrol treatments may be involved.

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