scholarly journals Microbial Community Structure in a Serpentine-Hosted Abiotic Gas Seepage at the Chimaera Ophiolite, Turkey

2017 ◽  
Vol 83 (12) ◽  
Author(s):  
Anna Neubeck ◽  
Li Sun ◽  
Bettina Müller ◽  
Magnus Ivarsson ◽  
Hakan Hosgörmez ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Community Structure ◽  
Archaeal Community ◽  
Resistant Bacteria ◽  
Rrna Gene ◽  
Content Type ◽  
Metal Levels ◽  
Gas Seepage ◽  
Points Of View

ABSTRACT The surface waters at the ultramafic ophiolitic outcrop in Chimaera, Turkey, are characterized by high pH values and high metal levels due to the percolation of fluids through areas of active serpentinization. We describe the influence of the liquid chemistry, mineralogy, and H2 and CH4 levels on the bacterial community structure in a semidry, exposed, ultramafic environment. The bacterial and archaeal community structures were monitored using Illumina sequencing targeting the 16S rRNA gene. At all sampling points, four phyla, Proteobacteria, Actinobacteria, Chloroflexi, and Acidobacteria, accounted for the majority of taxa. Members of the Chloroflexi phylum dominated low-diversity sites, whereas Proteobacteria dominated high-diversity sites. Methane, nitrogen, iron, and hydrogen oxidizers were detected as well as archaea and metal-resistant bacteria. IMPORTANCE Our study is a comprehensive microbial investigation of the Chimaera ophiolite. DNA has been extracted from 16 sites in the area and has been studied from microbial and geochemical points of view. We describe a microbial community structure that is dependent on terrestrial, serpentinization-driven abiotic H2, which is poorly studied due to the rarity of these environments on Earth.

scholarly journals Comparative Analysis of Bacterial and Archaeal Community Structure in Microwave Pretreated Thermophilic and Mesophilic Anaerobic Digesters Utilizing Mixed Sludge under Organic Overloading

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 887 ◽  
Author(s):  
Gokce Kor-Bicakci ◽  
Emine Ubay-Cokgor ◽  
Cigdem Eskicioglu
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Community Structure ◽  
High Throughput Sequencing ◽  
Biogas Production ◽  
Archaeal Community ◽  
Rrna Gene ◽  
Anaerobic Digesters ◽  
Pretreatment Conditions ◽  
The Impact

The effects of microwave (MW) pretreatment were investigated by six anaerobic digesters operated under thermophilic and mesophilic conditions at high organic loading rates (4.9–5.7 g volatile solids/L/d). The experiments and analyses were mainly designed to reveal the impact of MW pretreatment and digester temperatures on the process stability and microbial community structure by correlating the composition of microbial populations with volatile fatty acid (VFA) concentrations. A slight shift from biogas production (with a reasonable methane content) to VFA accumulation was observed in the thermophilic digesters, especially in the MW-irradiated reactors. Microbial population structure was assessed using a high-throughput sequencing of 16S rRNA gene on the MiSeq platform. Microbial community structure was slightly affected by different MW pretreatment conditions, while substantially affected by the digester temperature. The phylum Bacteroidetes proliferated in the MW-irradiated mesophilic digesters by resisting high-temperature MW (at 160 °C). Hydrogenotrophic methanogenesis (mostly the genus of Methanothermobacter) was found to be a key route of methane production in the thermophilic digesters, whereas aceticlastic methanogenesis (mostly the genus of Methanosaeta) was the main pathway in the mesophilic digesters.

scholarly journals Analysis of the Microbial Community Structure in Coastal Sediment of an Ascidian Farm in South Korea through 16S rRNA Gene Amplicon Sequencing

2021 ◽  
Vol 10 (30) ◽  
Author(s):  
Ilwon Jeong ◽  
Jong-Oh Kim ◽  
Seokjin Yoon ◽  
Kyunghoi Kim
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Microbial Community Structure ◽  
Amplicon Sequencing ◽  
Rrna Gene ◽  
Content Type ◽  
Styela Clava ◽  
Structure Changes

Aquaculture places contamination pressure on the coastal environment. We investigated the microbial community structure changes in sediment in an ascidian Styela clava farm. Data profiling of the 16S rRNA gene amplicon sequence shows that the microbial diversity of sediment in the Styela clava farm is dominated by Proteobacteria phyla (relative abundance, 95.34 to 97.85%).

scholarly journals Antibiotic resistome and microbial community structure during anaerobic co-digestion of food waste, paper and cardboard

2020 ◽  
Vol 96 (2) ◽  
Author(s):  
Kärt Kanger ◽  
Nigel G H Guilford ◽  
HyunWoo Lee ◽  
Camilla L Nesbø ◽  
Jaak Truu ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Solid State ◽  
Food Waste ◽  
Microbial Community Structure ◽  
Microbial Community Composition ◽  
Microbial Community Analysis ◽  
Waste Paper ◽  
Rrna Gene ◽  
Significant Shift

ABSTRACT Solid organic waste is a significant source of antibiotic resistance genes (ARGs) and effective treatment strategies are urgently required to limit the spread of antimicrobial resistance. Here, we studied ARG diversity and abundance as well as the relationship between antibiotic resistome and microbial community structure within a lab-scale solid-state anaerobic digester treating a mixture of food waste, paper and cardboard. A total of 10 samples from digester feed and digestion products were collected for microbial community analysis including small subunit rRNA gene sequencing, total community metagenome sequencing and high-throughput quantitative PCR. We observed a significant shift in microbial community composition and a reduction in ARG diversity and abundance after 6 weeks of digestion. ARGs were identified in all samples with multidrug resistance being the most abundant ARG type. Thirty-two per cent of ARGs detected in digester feed were located on plasmids indicating potential for horizontal gene transfer. Using metagenomic assembly and binning, we detected potential bacterial hosts of ARGs in digester feed, which included Erwinia, Bifidobacteriaceae, Lactococcus lactis and Lactobacillus. Our results indicate that the process of sequential solid-state anaerobic digestion of food waste, paper and cardboard tested herein provides a significant reduction in the relative abundance of ARGs per 16S rRNA gene.

scholarly journals Assessment of microbial communities in Nakivubo wetland and its catchment areas in Lake Victoria Basin, Uganda

2020 ◽  
Author(s):  
Bernard N. Kanoi ◽  
Maribet Gamboa ◽  
Doris Ngonzi ◽  
Thomas G. Egwang
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Diversity ◽  
Microbial Community Structure ◽  
Lake Victoria ◽  
Rrna Gene ◽  
Lake Victoria Basin ◽  
Structure Changes ◽  
Catchment Areas ◽  
Polluted Sites

AbstractMicrobial community structure changes are key in detecting and characterizing the impacts of anthropogenic activities on aquatic ecosystems. Here, we evaluated the effect of river pollution of industrial and urban sites on the microbial community composition and distribution in the Nakivubo wetland and its catchment areas in Lake Victoria basin, Uganda. Samples were collected from two industrial and one urban polluted sites and the microbial diversity was analyzed based on a 16S rRNA gene clone library. Differences in microbial diversity and community structure were observed at different sampling points. Bacteria associated with bioremediation were found in sites receiving industrial waste, while a low proportion of important human-pathogenic bacteria were seen in urban polluted sites. While Escherichia spp. was the most dominant genus of bacteria for all sites, three unique bacteria, Bacillus sp., Pseudomonas sp., Thermomonas sp., which have been reported to transform contaminants such as heavy metals and hydrocarbons (such as oils) by their metabolic pathways were also identified. Our results may serve as a basis for further studies assessing microbial community structure changes among polluted sites at Nakivubo Water Channel for management and monitoring. The diversity of natural microbial consortia could also be a rich bioprospecting resource for novel industrial enzymes, medicinal and bioactive compounds.

scholarly journals Natural Attenuation of Mn(II) in Metal Refinery Wastewater: Microbial Community Structure Analysis and Isolation of a New Mn(II)-Oxidizing Bacterium Pseudomonas sp. SK3

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 507 ◽  
Author(s):  
Santisak Kitjanukit ◽  
Kyohei Takamatsu ◽  
Naoko Okibe
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Structure Analysis ◽  
Microbial Community Structure ◽  
Natural Attenuation ◽  
Rrna Gene ◽  
Pseudomonas Sp ◽  
Refinery Wastewater ◽  
Pipe Surface

Natural attenuation of Mn(II) was observed inside the metal refinery wastewater pipeline, accompanying dark brown-colored mineralization (mostly MnIVO2 with some MnIII2O3 and Fe2O3) on the inner pipe surface. The Mn-deposit hosted the bacterial community comprised of Hyphomicrobium sp. (22.1%), Magnetospirillum sp. (3.2%), Geobacter sp. (0.3%), Bacillus sp. (0.18%), Pseudomonas sp. (0.03%), and non-metal-metabolizing bacteria (74.2%). Culture enrichment of the Mn-deposit led to the isolation of a new heterotrophic Mn(II)-oxidizer Pseudomonas sp. SK3, with its closest relative Ps. resinovorans (with 98.4% 16S rRNA gene sequence identity), which was previously unknown as an Mn(II)-oxidizer. Oxidation of up to 100 mg/L Mn(II) was readily initiated and completed by isolate SK3, even in the presence of high contents of MgSO4 (a typical solute in metal refinery wastewaters). Additional Cu(II) facilitated Mn(II) oxidation by isolate SK3 (implying the involvement of multicopper oxidase enzyme), allowing a 2-fold greater Mn removal rate, compared to the well-studied Mn(II)-oxidizer Ps. putida MnB1. Poorly crystalline biogenic birnessite was formed by isolate SK3 via one-electron transfer oxidation, gradually raising the Mn AOS (average oxidation state) to 3.80 in 72 h. Together with its efficient in vitro Mn(II) oxidation behavior, a high Mn AOS level of 3.75 was observed with the pipeline Mn-deposit sample collected in situ. The overall results, including the microbial community structure analysis of the pipeline sample, suggest that the natural Mn(II) attenuation phenomenon was characterized by robust in situ activity of Mn(II) oxidizers (including strain SK3) for continuous generation of Mn(IV). This likely synergistically facilitated chemical Mn(II)/Mn(IV) synproportionation for effective Mn removal in the complex ecosystem established in this artificial pipeline structure. The potential utility of isolate SK3 is illustrated for further industrial application in metal refinery wastewater treatment processes.

scholarly journals Effect of Drought Stress and Developmental Stages on Microbial Community Structure and Diversity in Peanut Rhizosphere Soil

2019 ◽  
Vol 20 (9) ◽  
pp. 2265 ◽  
Author(s):  
Liangxiang Dai ◽  
Guanchu Zhang ◽  
Zipeng Yu ◽  
Hong Ding ◽  
Yang Xu ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Drought Tolerance ◽  
Microbial Communities ◽  
Microbial Community Structure ◽  
Defense Mechanism ◽  
Developmental Stages ◽  
Rrna Gene ◽  
Special Importance ◽  
Arachis Hypogaea L

Background: Peanut (Arachis hypogaea L.), an important oilseed and food legume, is widely cultivated in the semi-arid tropics. Drought is the major stress in this region which limits productivity. Microbial communities in the rhizosphere are of special importance to stress tolerance. However, relatively little is known about the relationship between drought and microbial communities in peanuts. Method: In this study, deep sequencing of the V3-V4 region of the 16S rRNA gene was performed to characterize the microbial community structure of drought-treated and untreated peanuts. Results: Taxonomic analysis showed that Actinobacteria, Proteobacteria, Saccharibacteria, Chloroflexi, Acidobacteria and Cyanobacteria were the dominant phyla in the peanut rhizosphere. Comparisons of microbial community structure of peanuts revealed that the relative abundance of Actinobacteria and Acidobacteria dramatically increased in the seedling and podding stages in drought-treated soil, while that of Cyanobacteria and Gemmatimonadetes increased in the flowering stage in drought-treated rhizospheres. Metagenomic profiling indicated that sequences related to metabolism, signaling transduction, defense mechanism and basic vital activity were enriched in the drought-treated rhizosphere, which may have implications for plant survival and drought tolerance. Conclusion: This microbial communities study will form the foundation for future improvement of drought tolerance of peanuts via modification of the soil microbes.

PSIX-6 Dietary crude protein modifies fecal microbial populations independent of feed efficiency status in dairy cows

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 439-440
Author(s):  
Alvaro Morales ◽  
Leticia Campos ◽  
Jacquelyn Prestegaard ◽  
Kayla Alward ◽  
Connor Owens ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Community Structure ◽  
Feed Intake ◽  
Feed Efficiency ◽  
Crude Protein ◽  
High Energy ◽  
Repeated Measurements ◽  
Rrna Gene ◽  
Fecal Microbiome

Abstract Understanding the composition and structure of the fecal microbial community may provide insight into bacterial adaptation to dietary changes in cattle. The aim of this study was to determine relationships among the fecal microbiome, residual feed intake (RFI) and residual net energy intake (REI) with diets varying in crude protein (CP). Four Holstein lactating cows (806 ± 38 kg of BW) were randomly assigned to one of two treatments (LOW: 13.2% and BASE:16.6% CP) in a crossover design (2 periods of 18 d each). Cows were 260 ± 62 days in milk (DIM) and averaged 26.5 ± 12.0 kg milk yield (MY). Diets were formulated to meet animal needs. Individual feed intake measured by a Calan Gate system was used to calculate daily dry matter intake (DMI). BW, MY and milk components were also measured daily. A linear mixed model with repeated measurements over time was used to evaluate diet effect on DMI, MY, RFI and REI in SAS. Individual fecal samples were collected at the end of each period and extracted DNA was subject to 16S rRNA gene deep amplicon sequencing. Operational Taxonomic Units (OTU) were obtained using ≥97% similarity (SILVA database) and microbial community structure was assessed using alpha and beta diversity measures. No significant differences in phenotypic variables evaluated were observed between treatments or periods. We identified 927 concordant OTU among all cows, with 505 novel OTU identified in BASE cows and 403 in LOW cows. Microbial community structure was similar between treatments and feed efficiency measures. One OTU class, Erysipelotrichi, increased in abundance (P = 0.014) in BASE compared to LOW treatment. Findings reflect previous literature in which Erysipelotrichi was associated with high energy or high fat diets. Although no differences were observed in the phenotypic measurements between treatments, metagenomics analyses indicated differences in specific fecal microbial abundance.

scholarly journals Microbial Community Structure in the Sediments and Its Relation to Environmental Factors in Eutrophicated Sancha Lake

2019 ◽  
Vol 16 (11) ◽  
pp. 1931 ◽  
Author(s):  
Yong Li ◽  
Jiejie Zhang ◽  
Jianqiang Zhang ◽  
Wenlai Xu ◽  
Zishen Mou
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Total Phosphorus ◽  
Microbial Community Structure ◽  
High Throughput Sequencing ◽  
Pearson Correlation ◽  
Microbial Populations ◽  
Rrna Gene ◽  
Overlying Water ◽  
Four Seasons

To study the microbial community structure in sediments and its relation to eutrophication environment factors, the sediments and the overlying water of Sancha Lake were collected in the four seasons. MiSeq high-throughput sequencing was conducted for the V3–V4 hypervariable regions of the 16S rRNA gene and was used to analyze the microbial community structure in sediments. Pearson correlation and redundancy analysis (RDA) were conducted to determine the relation between microbial populations and eutrophic factors. The results demonstrated four main patterns: (1) in the 36 samples that were collected, the classification annotation suggested 64 phyla, 259 classes, 476 orders, 759 families, and 9325 OTUs; (2) The diversity indices were ordered according to their values as with summer > winter > autumn > spring; (3) The microbial populations in the four seasons belonged to two distinct characteristic groups; (4) pH, dissolved oxygen (DO), total phosphorus (TP), and total nitrogen (TN) had significant effects on the community composition and structure, which further affected the dissolved total phosphorus (DTP) significantly. The present study demonstrates that the microbial communities in Sancha Lake sediments are highly diverse, their compositions and distributions are significantly different between spring and non-spring, and Actinobacteria and Cyanobacteria may be the key populations or indicator organisms for eutrophication.

scholarly journals Effect of Elevated Salt Concentrations on the Aerobic Granular Sludge Process: Linking Microbial Activity with Microbial Community Structure

2011 ◽  
Vol 77 (22) ◽  
pp. 7942-7953 ◽  
Author(s):  
J. P. Bassin ◽  
M. Pronk ◽  
G. Muyzer ◽  
R. Kleerebezem ◽  
M. Dezotti ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Community Structure ◽  
Phosphorus Removal ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Granular Sludge ◽  
Phosphate Removal ◽  
Aerobic Granular Sludge ◽  
Nitrogen And Phosphorus ◽  
Content Type

ABSTRACTThe long- and short-term effects of salt on biological nitrogen and phosphorus removal processes were studied in an aerobic granular sludge reactor. The microbial community structure was investigated by PCR-denaturing gradient gel electrophoresis (DGGE) on 16S rRNA andamoAgenes. PCR products obtained from genomic DNA and from rRNA after reverse transcription were compared to determine the presence of bacteria as well as the metabolically active fraction of bacteria. Fluorescencein situhybridization (FISH) was used to validate the PCR-based results and to quantify the dominant bacterial populations. The results demonstrated that ammonium removal efficiency was not affected by salt concentrations up to 33 g/liter NaCl. Conversely, a high accumulation of nitrite was observed above 22 g/liter NaCl, which coincided with the disappearance ofNitrospirasp. Phosphorus removal was severely affected by gradual salt increase. No P release or uptake was observed at steady-state operation at 33 g/liter NaCl, exactly when the polyphosphate-accumulating organisms (PAOs), “CandidatusAccumulibacter phosphatis” bacteria, were no longer detected by PCR-DGGE or FISH. Batch experiments confirmed that P removal still could occur at 30 g/liter NaCl, but the long exposure of the biomass to this salinity level was detrimental for PAOs, which were outcompeted by glycogen-accumulating organisms (GAOs) in the bioreactor. GAOs became the dominant microorganisms at increasing salt concentrations, especially at 33 g/liter NaCl. In the comparative analysis of the diversity (DNA-derived pattern) and the activity (cDNA-derived pattern) of the microbial population, the highly metabolically active microorganisms were observed to be those related to ammonia (Nitrosomonassp.) and phosphate removal (“CandidatusAccumulibacter”).

scholarly journals Structural changes in the oral microbiome of the adolescent patients with moderate or severe dental fluorosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Qian Wang ◽  
Xuelan Chen ◽  
Huan Hu ◽  
Xiaoyuan Wei ◽  
Xiaofan Wang ◽  
...  
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Microbial Community Structure ◽  
Structural Changes ◽  
Dental Fluorosis ◽  
Bacterial Species ◽  
Fusobacterium Nucleatum ◽  
Oral Microbiome ◽  
Rrna Gene ◽  
Oral Diseases

AbstractDental fluorosis is a very prevalent endemic disease. Although oral microbiome has been reported to correlate with different oral diseases, there appears to be an absence of research recognizing any relationship between the severity of dental fluorosis and the oral microbiome. To this end, we investigated the changes in oral microbial community structure and identified bacterial species associated with moderate and severe dental fluorosis. Salivary samples of 42 individuals, assigned into Healthy (N = 9), Mild (N = 14) and Moderate/Severe (M&S, N = 19), were investigated using the V4 region of 16S rRNA gene. The oral microbial community structure based on Bray Curtis and Weighted Unifrac were significantly changed in the M&S group compared with both of Healthy and Mild. As the predominant phyla, Firmicutes and Bacteroidetes showed variation in the relative abundance among groups. The Firmicutes/Bacteroidetes (F/B) ratio was significantly higher in the M&S group. LEfSe analysis was used to identify differentially represented taxa at the species level. Several genera such as Streptococcus mitis, Gemella parahaemolysans, Lactococcus lactis, and Fusobacterium nucleatum, were significantly more abundant in patients with moderate/severe dental fluorosis, while Prevotella melaninogenica and Schaalia odontolytica were enriched in the Healthy group. In conclusion, our study indicates oral microbiome shift in patients with moderate/severe dental fluorosis. We identified several differentially represented bacterial species enriched in moderate and severe fluorosis. Findings from this study suggests that the roles of these bacteria in oral health and related diseases warrant more consideration in patients with moderate and severe fluorosis.

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