Microbial community dynamics in the forefield of glaciers

Retreating ice fronts (as a result of a warming climate) expose large expanses of deglaciated forefield, which become colonized by microbes and plants. There has been increasing interest in characterizing the biogeochemical development of these ecosystems using a chronosequence approach. Prior to the establishment of plants, microbes use autochthonously produced and allochthonously delivered nutrients for growth. The microbial community composition is largely made up of heterotrophic microbes (both bacteria and fungi), autotrophic microbes and nitrogen-fixing diazotrophs. Microbial activity is thought to be responsible for the initial build-up of labile nutrient pools, facilitating the growth of higher order plant life in developed soils. However, it is unclear to what extent these ecosystems rely on external sources of nutrients such as ancient carbon pools and periodic nitrogen deposition. Furthermore, the seasonal variation of chronosequence dynamics and the effect of winter are largely unexplored. Modelling this ecosystem will provide a quantitative evaluation of the key processes and could guide the focus of future research. Year-round datasets combined with novel metagenomic techniques will help answer some of the pressing questions in this relatively new but rapidly expanding field, which is of growing interest in the context of future large-scale ice retreat.

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Analysis of Microbial Community Dynamics during the Acclimatization Period of a Membrane Bioreactor Treating Table Olive Processing Wastewater

Applied Sciences ◽

10.3390/app9183647 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3647 ◽

Cited By ~ 1

Author(s):

Sotiris I. Patsios ◽

Sofia Michailidou ◽

Konstantinos Pasentsis ◽

Antonios M. Makris ◽

Anagnostis Argiriou ◽

...

Keyword(s):

Microbial Community ◽

Biological Treatment ◽

Large Scale ◽

Membrane Bioreactor ◽

Community Dynamics ◽

Metabolic Adaptation ◽

Process Step ◽

Microbial Community Dynamics ◽

Table Olive ◽

Acclimatization Period

Biological treatment of table olive processing wastewater (TOPW) may be problematic due to its high organic and polyphenolic compound content. Biomass acclimatization is a necessary, yet sensitive, stage for efficient TOPW biological treatment. Next-generation sequencing technologies can provide valuable insights into this critical process step. An aerobic membrane bioreactor (MBR) system, initially inoculated with municipal activated sludge, was acclimatized to treat TOPW. Operational stability and bioremediation efficiency were monitored for approx. three months, whereas microbial community dynamics and metabolic adaptation were assessed through metagenomic and metatranscriptomic analysis. A swift change was identified in both the prokaryotic and eukaryotic bio-community after introduction of TOPW in the MBR, and a new diverse bio-community was established. Thauera and Paracoccus spp. are dominant contributors to the metabolic activity of the stable bio-community, which resulted in over 90% and 85% removal efficiency of total organic carbon and total polyphenols, respectively. This is the first study assessing the microbial community dynamics in a well-defined MBR process treating TOPW, offering guidance in the start-up of large-scale applications.

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Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

SOIL ◽

10.5194/soil-2-487-2016 ◽

2016 ◽

Vol 2 (3) ◽

pp. 487-498 ◽

Cited By ~ 13

Author(s):

Belinda C. Martin ◽

Suman J. George ◽

Charles A. Price ◽

Esmaeil Shahsavari ◽

Andrew S. Ball ◽

...

Keyword(s):

Microbial Community ◽

Microbial Activity ◽

Community Dynamics ◽

Denaturing Gradient Gel Electrophoresis ◽

Plant Root ◽

Root Exudation ◽

Microbial Community Composition ◽

Gas Chromatography Mass Spectrometry ◽

Potential Implication ◽

Microbial Community Dynamics

Abstract. Petroleum hydrocarbons (PHCs) are among the most prevalent sources of environmental contamination. It has been hypothesized that plant root exudation of low molecular weight organic acid anions (carboxylates) may aid degradation of PHCs by stimulating heterotrophic microbial activity. To test their potential implication for bioremediation, we applied two commonly exuded carboxylates (citrate and malonate) to uncontaminated and diesel-contaminated microcosms (10 000 mg kg−1; aged 40 days) and determined their impact on the microbial community and PHC degradation. Every 48 h for 18 days, soil received 5 µmol g−1 of (i) citrate, (ii) malonate, (iii) citrate + malonate or (iv) water. Microbial activity was measured daily as the flux of CO2. After 18 days, changes in the microbial community were assessed by a community-level physiological profile (CLPP) and 16S rRNA bacterial community profiles determined by denaturing gradient gel electrophoresis (DGGE). Saturated PHCs remaining in the soil were assessed by gas chromatography–mass spectrometry (GC-MS). Cumulative soil respiration increased 4- to 6-fold with the addition of carboxylates, while diesel contamination resulted in a small, but similar, increase across all carboxylate treatments. The addition of carboxylates resulted in distinct changes to the microbial community in both contaminated and uncontaminated soils but only a small increase in the biodegradation of saturated PHCs as measured by the n-C17 : pristane biomarker. We conclude that while the addition of citrate and malonate had little direct effect on the biodegradation of saturated hydrocarbons present in diesel, their effect on the microbial community leads us to suggest further studies using a variety of soils and organic acids, and linked to in situ studies of plants, to investigate the role of carboxylates in microbial community dynamics.

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Microbial Community Dynamics Associated with Rhizosphere Carbon Flow

Applied and Environmental Microbiology ◽

10.1128/aem.69.11.6793-6800.2003 ◽

2003 ◽

Vol 69 (11) ◽

pp. 6793-6800 ◽

Cited By ~ 232

Author(s):

Jessica L. Butler ◽

Mark A. Williams ◽

Peter J. Bottomley ◽

David D. Myrold

Keyword(s):

Microbial Community ◽

Growth Stage ◽

Shoot Growth ◽

Community Dynamics ◽

Lolium Multiflorum ◽

Microbial Community Composition ◽

Gram Positive ◽

Soil Microbial ◽

Microbial Community Dynamics ◽

Period 2

ABSTRACT Root-deposited photosynthate (rhizodeposition) is an important source of readily available carbon (C) for microbes in the vicinity of growing roots. Plant nutrient availability is controlled, to a large extent, by the cycling of this and other organic materials through the soil microbial community. Currently, our understanding of microbial community dynamics associated with rhizodeposition is limited. We used a 13C pulse-chase labeling procedure to examine the incorporation of rhizodeposition into individual phospholipid fatty acids (PLFAs) in the bulk and rhizosphere soils of greenhouse-grown annual ryegrass (Lolium multiflorum Lam. var. Gulf). Labeling took place during a growth stage in transition between active root growth and rapid shoot growth on one set of plants (labeling period 1) and 9 days later during the rapid shoot growth stage on another set of plants (labeling period 2). Temporal differences in microbial community composition were more apparent than spatial differences, with a greater relative abundance of PLFAs from gram-positive organisms (i15:0 and a15:0) in the second labeling period. Although more abundant, gram-positive organisms appeared to be less actively utilizing rhizodeposited C in labeling period 2 than in labeling period 1. Gram-negative bacteria associated with the 16:1ω5 PLFA were more active in utilizing 13C-labeled rhizodeposits in the second labeling period than in the first labeling period. In both labeling periods, however, the fungal PLFA 18:2ω6,9 was the most highly labeled. These results demonstrate the effectiveness of using 13C labeling and PLFA analysis to examine the microbial dynamics associated with rhizosphere C cycling by focusing on the members actively involved.

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The effect of stream microbial inoculation on in-stream carbon processing

10.5194/egusphere-egu2020-20555 ◽

2020 ◽

Author(s):

Jakob Schelker ◽

Florian Caillon ◽

Katharina Besemer ◽

Peter Peduzzi ◽

Astrid Harjung

Keyword(s):

Microbial Community ◽

Community Dynamics ◽

Soil Microbes ◽

Microbial Community Composition ◽

Microbial Life ◽

Soil Microbial ◽

Microbial Inoculation ◽

Microbial Community Dynamics ◽

Small Streams ◽

Carbon Processing

<p>Hydrological events mobilize chemically diverse dissolved organic matter (DOM) from soils to streams. Further, such events can also cause an influx of soil microbial life into fluvial systems. Here we present results from the HYDRO-DIVERSITY project, which aims to investigate the dynamic transfer of DOM and microbial life from catchment soils to streams, as well as their downstream fate. We studied the microbial community composition and DOM quality using 16S Illumina sequencing and fluorescence and absorbance spectroscopy. Data from small streams showed strong changes in DOM composition and in the microbial community delivered from soils during hydrological events. Moreover, we performed a flume experiment, in which soil microbial inoculation and the processing of DOM across different biofilm ages were evaluated. As such, biofilm age did not directly affect the establishment of soil microbes in the stream ecosystem. However, in-stream processing of soil DOM appeared to be affected by the inoculation event. This poses the fundamental question, if the processing of DOM in streams and rivers depends on the transient presence of specific soil microbes in stream ecosystems. Overall our results show that soils provide a dynamic and relevant influx of microbes and DOM to first order streams and that this dynamic influx likely affects microbial community dynamics of downstream fluvial networks as well as in-stream DOM processing.&#160;</p>

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A Long-Standing Complex Tropical Dipole Shapes Marine Microbial Biogeography

Applied and Environmental Microbiology ◽

10.1128/aem.00614-18 ◽

2018 ◽

Vol 84 (18) ◽

Cited By ~ 3

Author(s):

Wei Yan ◽

Rui Zhang ◽

Nianzhi Jiao

Keyword(s):

Community Structure ◽

Microbial Community ◽

Microbial Communities ◽

Large Scale ◽

Community Dynamics ◽

Anticyclonic Eddy ◽

Cyclonic Eddy ◽

Content Type ◽

Microbial Community Dynamics ◽

Biogeographic Provinces

ABSTRACTMicrobial population size, production, diversity, and community structure are greatly influenced by the surrounding physicochemical conditions, such as large-scale biogeographic provinces and water masses. An oceanic mesoscale dipole consists of a cyclonic eddy and an anticyclonic eddy. Dipoles occur frequently in the ocean and usually last from a few days to several months; they have significant impacts on local and global oceanic biological, ecological, and geochemical processes. To better understand how dipoles shape microbial communities, we examined depth-resolved distributions of microbial communities across a dipole in the South China Sea. Our data demonstrated that the dipole had a substantial influence on microbial distributions, community structure, and functional groups both vertically and horizontally. Large alpha and beta diversity differences were observed between anticyclonic and cyclonic eddies in surface and subsurface layers, consistent with distribution changes of major bacterial groups in the dipole. The dipole created uplift, downward transport, enrichment, depletion, and horizontal transport effects. We also found that the edge of the dipole might induce strong subduction, indicated by the presence ofProchlorococcusandSynechococcusin deep waters. Our findings suggest that dipoles, with their unique characteristics, might act as a driver for microbial community dynamics.IMPORTANCEOceanic dipoles, which consist of a cyclonic eddy and an anticyclonic eddy together, are among the most contrasted phenomena in the ocean. Dipoles generate strong vertical mixing and horizontal advection, inducing biological responses. This study provides vertical profiles of microbial abundance, diversity, and community structure in a mesoscale dipole. We identify the links between the physical oceanography and microbial oceanography and demonstrate that the dipole, with its unique features, could act as a driver for microbial community dynamics, which may have large impacts on both the local and global marine biogeochemical cycles.

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The human female urogenital microbiome: complexity in normality

Emerging Topics in Life Sciences ◽

10.1042/etls20170042 ◽

2017 ◽

Vol 1 (4) ◽

pp. 363-372 ◽

Cited By ~ 6

Author(s):

David A. MacIntyre ◽

Lynne Sykes ◽

Phillip R. Bennett

Keyword(s):

Microbial Community ◽

Community Dynamics ◽

Biomarker Discovery ◽

Disease Risk ◽

Microbial Community Composition ◽

Female Genital Tract ◽

External Genitalia ◽

Urogenital Tract ◽

Host Interactions ◽

Microbial Community Dynamics

Microbial communities of the urogenital tract have long been recognised to play an important role in disease states. A revolution in methodological approaches is permitting the assessment of complex urogenital tract microbiota–host interactions and the metabolic and protein milieu of the mucosal interface. There is now great potential for significant advances in biomarker discovery and disease risk stratification, and for the elucidation of mechanisms underpinning the microbial community dynamics involved in urogenital tract pathology. Microbiota–host interactions in the female genital tract have a particular significance, because unlike in the male, there is direct communication between the external genitalia, the uterus and the peritoneal cavity. This review examines the microbial community composition at differing sites of the female urogenital tract and its relationship with health and disease. Key factors involved in the modulation of vaginal microbiome stability and structure, such as endocrine, immune and inflammatory pathways, are considered in the context of a woman's life cycle and disease pathogenesis.

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Influence of the Depth and Season on Microbial Community Dynamics of the Black Sea

10.21203/rs.3.rs-693853/v1 ◽

2021 ◽

Author(s):

Rafet Cagri Ozturk ◽

Ilhan Altinok ◽

Ali Muzaffer Feyzioglu ◽

Erol Capkin ◽

Ilknur Yildiz

Keyword(s):

Microbial Community ◽

Community Composition ◽

Black Sea ◽

Community Dynamics ◽

Microbial Community Composition ◽

The Black Sea ◽

Ecological Niches ◽

Rrna Gene ◽

Similar Species ◽

Microbial Community Dynamics

Abstract The Black Sea is a unique environment having a thin layer of oxic-zone above and anoxic-zone below. Seasonal, vertical, and horizontal microbial assemblages were studied in terms of diversity, abundance, community structure using NGS of the 16S rRNA gene. Total of 750 bacteria species from 23 different phyla were identified. The number of species richness increased from the surface to deeper zones. Although microbial community compositions between sampling stations were similar, microbial community compositions were significantly different vertically between zones. Community compositions of the seawater and sediment were also significantly different. Community composition at 5 meters in summer was significantly different from other seasons, while remaining depths appeared similar. Species of nitrite-oxidizing, sulfate-reducing, thiosulfate reducing, Iron-reducing, Fe-Mn reducing and electricity-producing bacteria were reported for the first time in the Black Sea. Proteobacteria dominated all the sampling depths. Proteobacteria, Cyanobacteria, Bacteroidetes, and Verrucomicrobia were present in the whole water column, while Nitrospinae, Chloroflexi, and Kiritimatiellaeota were restricted, appearing abundant at 75 meters and deeper layers. Vertical microbial community composition variation is attributable to environmental factors and their adaptations to the various ecological niches.

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The influence of microbial community dynamics on anaerobic digestion efficiency and stability: A Review

International Journal of Renewable Energy Development ◽

10.14710/ijred.9.1.85-95 ◽

2020 ◽

Vol 9 (1) ◽

pp. 85-95

Author(s):

Yumechris Amekan

Keyword(s):

Microbial Community ◽

Anaerobic Digestion ◽

Community Composition ◽

Energy Recovery ◽

Volatile Fatty Acids ◽

Community Dynamics ◽

Microbial Community Composition ◽

Microbial Community Dynamics ◽

Stable Performance ◽

Microbial Groups

An essential component in sustainable energy development is the production of bioenergy from waste. The most successful bioenergy technology worldwide is anaerobic digestion (AD), which is a microbially-mediated process of organic feedstock conversion into energy-rich compounds (volatile fatty acids (VFA) and biogas) for renewable energy generation. AD is deployed in a range of situations including systems for on-farm energy recovery from animal and plant waste to the processing of food and municipal solid waste (with the additional benefit of land-fill reduction).Anaerobic digesters rely on a diverse microbial community working syntrophycally through a series of interrelated biochemical processes.Each stage in anaerobic digestion is carried out by different microbial groups. Thus, to optimise energy recovery from the AD process, the microbial community must have stable performance over time, balancing the various metabolic functions and taxonomic community composition in digesters. Complicating this balance, it has been found that the presence of ammonia, sulphate, and hydrogen sulphide in substantial concentrations often cause failure in the AD process. Thus, these substances cause adverse shifts in microbial community composition and/or inhibit bacterial growth, that influencing AD performance. ©2020. CBIORE-IJRED. All rights reserved

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