scholarly journals Pollution Gradients Altered the Bacterial Community Composition and Stochastic Process of Rural Polluted Ponds

2020 ◽  
Vol 8 (2) ◽  
pp. 311
Author(s):  
Xin Tai ◽  
Rui Li ◽  
Bao Zhang ◽  
Hao Yu ◽  
Xiao Kong ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Microbial Communities ◽  
Community Composition ◽  
Community Assembly ◽  
High Throughput Sequencing ◽  
Bacterial Community Composition ◽  
Rrna Gene ◽  
Sediment Samples ◽  
Pollution Levels ◽  
Water And Sediment

Understanding the effects of pollution on ecological communities and the underlying mechanisms that drive them will helpful for selecting a method to mediate polluted ecosystems. Quantifying the relative importance of deterministic and stochastic processes is a very important issue in ecology. However, little is known about their effects on the succession of microbial communities in different pollution levels rural ponds. Also, the processes that govern bacterial communities in polluted ponds are poorly understood. In this study, the microbial communities in water and sediment from the ponds were investigated by using the 16S rRNA gene high-throughput sequencing technology. Meanwhile, we used null model analyses based on a taxonomic and phylogenetic metrics approach to test the microbial community assembly processes. Pollution levels were found to significantly alter the community composition and diversity of bacteria. In the sediment samples, the bacterial diversity indices decreased with increasing pollutant levels. Between-community analysis revealed that community assembly processes among water and sediment samples stochastic ratio both gradually decreased with the increased pollution levels, indicating a potential deterministic environmental filtering that is elicited by pollution. Our results identified assemblage drivers of bacterial community is important for improving the efficacies of ecological evaluation and remediation for contaminated freshwater systems.

scholarly journals Correlation of Breed, Growth Performance, and Rumen Microbiota in Two Rustic Cattle Breeds Reared Under Different Conditions

2021 ◽  
Vol 12 ◽  
Author(s):  
Matteo Daghio ◽  
Francesca Ciucci ◽  
Arianna Buccioni ◽  
Alice Cappucci ◽  
Laura Casarosa ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Growth Performance ◽  
Community Composition ◽  
Lipid Composition ◽  
High Throughput Sequencing ◽  
Bacterial Community Composition ◽  
Daily Weight Gain ◽  
Rrna Gene ◽  
Rumen Microbiota ◽  
Cattle Breeds

The use of rustic cattle is desirable to face challenges brought on by climate change. Maremmana (MA) and Aubrac (AU) are rustic cattle breeds that can be successfully used for sustainable production. In this study, correlations between two rearing systems (feedlot and grazing) and the rumen microbiota, the lipid composition of rumen liquor (RL), and the growth performance of MA and AU steers were investigated. Bacterial community composition was characterized by high-throughput sequencing of 16S rRNA gene amplicons, and the RL lipid composition was determined by measuring fatty acid (FA) and the dimethyl acetal profiles. The main factor influencing bacterial community composition was the cattle breed. Some bacterial groups were positively correlated to average daily weight gain for the two breeds (i.e., Rikenellaceae RC9 gut group, Fibrobacter and Succiniclasticum in the rumen of MA steers, and Succinivibrionaceae UCG-002 in the rumen of AU steers); despite this, animal performance appeared to be influenced by short chain FAs production pathways and by the presence of H2 sinks that divert the H2 to processes alternative to the methanogenesis.

scholarly journals Fate of Antibiotic Resistance Genes in Abandoned Swine Feedlots in China: Seasonal Variation

2021 ◽  
Author(s):  
Na Li ◽  
Jianguo Chen ◽  
Chong Liu ◽  
Binxu Li ◽  
Changxiong Zhu ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Seasonal Variation ◽  
Bacterial Community ◽  
Community Composition ◽  
Resistance Genes ◽  
High Throughput Sequencing ◽  
Bacterial Community Composition ◽  
Antibiotic Resistance Genes ◽  
Rrna Gene ◽  
Variation Patterns

Abstract Background: Environmental hygiene concerns are needed to be settled before the reuse of abandoned swine feedlot sites. However, few researchers have focused on the fate of antibiotic resistance genes (ARGs) in soil microbiota around abandoned swine feedlots. In this study, we examined the seasonal alterations of ARGs and bacterial community composition in soil using quantitative PCR and high-throughput sequencing of 16S rRNA gene. Results: The seasonal variation patterns were different for different ARG subtypes and soil sampling sites. The bacterial community composition at the genus level generally showed no significant alteration from winter to summer. Moreover, the co-occurrence network suggested that the bacterial genera host range of ARGs was broader in the summer than in the winter. Conclusion: This study offers further data on ARG transfer risk in soil, emphasizing the necessity of continuous concern before reuse of abandoned feedlots.

scholarly journals Characteristics of planktonic and sediment bacterial communities in a heavily polluted urban river

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10866
Author(s):  
Heqing Huang ◽  
Jianhui Liu ◽  
Fanghui Zhang ◽  
Kangwen Zhu ◽  
Chunhua Yang ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Bacterial Communities ◽  
High Throughput Sequencing ◽  
Bacterial Community Composition ◽  
Urban River ◽  
Urban Rivers ◽  
Sediment Samples ◽  
Water And Sediment ◽  
Sediment Bacterial Communities ◽  
Water And Sediment Samples

Urban rivers represent a unique ecosystem in which pollution occurs regularly, altering the biogeochemical characteristics of waterbodies and sediments. However, little is presently known about the spatiotemporal patterns of planktonic and sediment bacterial community diversities and compositions in urban rivers. Herein, Illumina MiSeq high-throughput sequencing was performed to reveal the spatiotemporal dynamics of bacterial populations in Liangtan River, a heavily polluted urban river in Chongqing City (China). The results showed the richness and diversity of sediment bacteria were significantly higher than those of planktonic bacteria, whereas a strong overlap (46.7%) in OTUs was identified between water and sediment samples. Bacterial community composition remarkably differed in waters and sediments. Planktonic bacterial communities were dominated by Proteobacteria, Bacteroidetes, Cyanobacteria and Actinobacteria, while sediment bacterial communities mainly included Proteobacteria, Actinobacteria, Chloroflexi and Bacteroidetes. Additionally, several taxonomic groups of potential bacterial pathogens showed an increasing trend in water and sediment samples from residential and industrial areas (RI). Variation partition analysis (VPA) indicated that temperature and nutrient were identified as the main drivers determining the planktonic and sediment bacterial assemblages. These results highlight that bacterial communities in the polluted urban river exhibit spatiotemporal variation due to the combined influence of environmental factors associated with sewage discharge and hydropower dams.

scholarly journals Metagenomic Characterization of Bacterial Communities on Ready-to-Eat Vegetables and Effects of Household Washing on their Diversity and Composition

Pathogens ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 37 ◽  
Author(s):  
Soultana Tatsika ◽  
Katerina Karamanoli ◽  
Hera Karayanni ◽  
Savvas Genitsaris
Keyword(s):  
Bacterial Community ◽  
Community Composition ◽  
High Throughput Sequencing ◽  
Bacterial Community Composition ◽  
Rrna Gene ◽  
Human Pathogens ◽  
Storage Duration ◽  
Point Of Sale ◽  
Operational Taxonomic Units ◽  
High Level

Ready-to-eat (RTE) leafy salad vegetables are considered foods that can be consumed immediately at the point of sale without further treatment. The aim of the study was to investigate the bacterial community composition of RTE salads at the point of consumption and the changes in bacterial diversity and composition associated with different household washing treatments. The bacterial microbiomes of rocket and spinach leaves were examined by means of 16S rRNA gene high-throughput sequencing. Overall, 886 Operational Taxonomic Units (OTUs) were detected in the salads’ leaves. Proteobacteria was the most diverse high-level taxonomic group followed by Bacteroidetes and Firmicutes. Although they were processed at the same production facilities, rocket showed different bacterial community composition than spinach salads, mainly attributed to the different contributions of Proteobacteria and Bacteroidetes to the total OTU number. The tested household decontamination treatments proved inefficient in changing the bacterial community composition in both RTE salads. Furthermore, storage duration of the salads at refrigeration temperatures affected the microbiome, by decreasing the bacterial richness and promoting the dominance of psychrotropic bacteria. Finally, both salads were found to be a reservoir of opportunistic human pathogens, while washing methods usually applied at home proved to be inefficient in their removal.

Potential Oxygen Consumption and Community Composition of Sediment Bacteria in a Seasonally Hypoxic Enclosed Bay

2021 ◽  
Author(s):  
Fumiaki Mori ◽  
Yu Umezawa ◽  
Ruji Kondo ◽  
Gregory N. Nishihara ◽  
Minoru Wada
Keyword(s):  
Oxygen Consumption ◽  
Bacterial Community ◽  
Community Composition ◽  
Bacterial Community Composition ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Sediment Surface ◽  
Tetrazolium Chloride ◽  
Sediment Samples ◽  
Potential Oxygen

Abstract The dynamics of potential oxygen consumption at the sediment surface in a seasonally hypoxic bay were monitored monthly by applying a tetrazolium dye (2-(4-iodophenyl)-3-(4-nitrophenyl)-5-phenyl-2H-tetrazolium chloride [INT]) reduction assay to intact sediment core samples for two consecutive years (2012–2013). Based on the empirically determined correlation between INT reduction (INT-formazan formation) and actual oxygen consumption of sediment samples, we inferred the relative contribution of biological and non-biological (chemical) processes to the potential whole oxygen consumption in the collected sediment samples. It was demonstrated that both potentials consistently increased and reached a maximum during summer hypoxia in each year. For samples collected in 2012, amplicon sequence variants (ASVs) of the bacterial 16S rRNA genes derived from the sediment surface revealed a notable shift in the bacterial community composition before and after the INT assay incubation. Within the bacterial community that was predominated by the ASVs closely related to Woeseia (Woeseiaceae, Gammaproteobacteria), the relative abundance of ASVs affiliated with Arcobacter (Arcobacteraceae, Campylobacteria), a putative sulfur-oxidizing bacterial genus, increased markedly in the summer samples. These findings have implications not only for the group of bacteria that are consistently responsible for the consumption of dissolved oxygen (DO) year-round in the sediment, but also for those that might grow rapidly in response to episodic DO supply on the sediment surface during midst of seasonal hypoxia.

Dynamics of the bacterial community in a channel catfish nursery pond with a cage–pond integration system

2018 ◽  
Vol 64 (12) ◽  
pp. 954-967 ◽  
Author(s):  
Liqiang Zhong ◽  
Daming Li ◽  
Minghua Wang ◽  
Xiaohui Chen ◽  
Wenji Bian ◽  
...  
Keyword(s):  
Bacterial Community ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Community Composition ◽  
Channel Catfish ◽  
Bacterial Community Composition ◽  
Rrna Gene ◽  
Integration System ◽  
Nursery Pond ◽  
Site Variation

The changes in the bacterial community composition in a channel catfish nursery pond with a cage–pond integration system were investigated by sequencing of the 16S rRNA gene through Illumina MiSeq sequencing platforms. A total of 1 362 877 sequences and 1440 operational taxonomic units were obtained. Further analysis showed that the dominant phyla in the cage and pond groups were similar, including Actinobacteria, Cyanobacteria, Proteobacteria, and Bacteroidetes, although a significant difference was detected between them by ANOSIM (P < 0.05). Temporal changes and site variation were significantly related to the variation of the bacterial community. A comprehensive analysis of the diversity and evenness of the bacterial 16S rRNA gene, redundancy analysis (RDA), and partial Mantel test showed that the bacterial community composition in a cage–pond integration system was shaped more by temporal variation than by site variation. RDA also indicated that water temperature, total dissolved solids, and Secchi depth had the largest impact on bacterial populations.

scholarly journals Bacterial Community Composition in Central European Running Waters Examined by Temperature Gradient Gel Electrophoresis and Sequence Analysis of 16S rRNA Genes

2007 ◽  
Vol 74 (1) ◽  
pp. 188-199 ◽  
Author(s):  
Sara Beier ◽  
Karl-Paul Witzel ◽  
Jürgen Marxsen
Keyword(s):  
Sequence Analysis ◽  
Temperature Gradient ◽  
Bacterial Community ◽  
Community Composition ◽  
Gel Electrophoresis ◽  
Stream Water ◽  
Bacterial Community Composition ◽  
Water And Sediment ◽  
Gradient Gel Electrophoresis ◽  
Temperature Gradient Gel Electrophoresis

ABSTRACT The bacterial community composition in small streams and a river in central Germany was examined by temperature gradient gel electrophoresis (TGGE) with PCR products of 16S rRNA gene fragments and sequence analysis. Complex TGGE band patterns suggested high levels of diversity of bacterial species in all habitats of these environments. Cluster analyses demonstrated distinct differences among the communities in stream and spring water, sandy sediments, biofilms on stones, degrading leaves, and soil. The differences between stream water and sediment were more significant than those between sites within the same habitat along the stretch from the stream source to the mouth. TGGE data from an entire stream course suggest that, in the upper reach of the stream, a special suspended bacterial community is already established and changes only slightly downstream. The bacterial communities in water and sediment in an acidic headwater with a pH below 5 were highly similar to each other but deviated distinctly from the communities at the other sites. As ascertained by nucleotide sequence analysis, stream water communities were dominated by Betaproteobacteria (one-third of the total bacteria), whereas sediment communities were composed mainly of Betaproteobacteria and members of the Fibrobacteres/Acidobacteria group (each accounting for about 25% of bacteria). Sequences obtained from bacteria from water samples indicated the presence of typical cosmopolitan freshwater organisms. TGGE bands shared between stream and soil samples, as well as sequences found in bacteria from stream samples that were related to those of soil bacteria, demonstrated the occurrence of some species in both stream and soil habitats. Changes in bacterial community composition were correlated with geographic distance along a stream, but in comparisons of different streams and rivers, community composition was correlated only with environmental conditions.

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