scholarly journals Changes in Bacterial Community Structure in the Colon of Pigs Fed Different Experimental Diets and after Infection with Brachyspira hyodysenteriae

2000 ◽  
Vol 66 (8) ◽  
pp. 3290-3296 ◽  
Author(s):  
Thomas D. Leser ◽  
Rikke Hvid Lindecrona ◽  
Tim K. Jensen ◽  
Bent B. Jensen ◽  
Kristian Møller

ABSTRACT Bacterial communities in the large intestines of pigs were compared using terminal restriction fragment length polymorphism (T-RFLP) analysis targeting the 16S ribosomal DNA. The pigs were fed different experimental diets based on either modified standard feed or cooked rice supplemented with dietary fibers. After feeding of the animals with the experimental diets for 2 weeks, differences in the bacterial community structure in the spiral colon were detected in the form of different profiles of terminal restriction fragments (T-RFs). Some of the T-RFs were universally distributed, i.e., they were found in all samples, while others varied in distribution and were related to specific diets. The reproducibility of the T-RFLP profiles between individual animals within the diet groups was high. In the control group, the profiles remained unchanged throughout the experiment and were similar between two independent but identical experiments. When the animals were experimentally infected with Brachyspira hyodysenteriae, causing swine dysentery, many of the T-RFs fluctuated, suggesting a destabilization of the microbial community.

2003 ◽  
Vol 69 (10) ◽  
pp. 6018-6024 ◽  
Author(s):  
Dirk Schmitt-Wagner ◽  
Michael W. Friedrich ◽  
Bianca Wagner ◽  
Andreas Brune

ABSTRACT The highly compartmentalized gut of soil-feeding termites is characterized by pronounced axial dynamics in physicochemical conditions and microbial processes. In a companion paper (D. Schmitt-Wagner, M. W. Friedrich, B. Wagner, and A. Brune, Appl. Environ. Microbiol. 69:6007-6017, 2003), we demonstrated that the variety of physicochemical conditions in the different gut compartments of Cubitermes spp. is reflected in the diversity of the respective intestinal microbial communities. Here, we used molecular fingerprints of 16S rRNA genes of the bacterial community, obtained by terminal restriction fragment length polymorphism (T-RFLP) analysis, to describe the axial dynamics of the bacterial community structure in the different gut sections. Comparison of the T-RFLP profiles with the predicted terminal restriction fragments of the clones in clone libraries of the gut segments in Cubitermes orthognathus confirmed that all hindgut sections harbored distinct bacterial communities. Morisita indices of community similarity, calculated by comparing the different patterns, revealed large differences between the bacterial communities of soil, gut, and nest material and also among the individual gut sections. By contrast, comparison of the homologous gut segments of different Cubitermes species indicated that the three termite species investigated possessed a similar, gut-specific microbiota that remained comparatively stable even during several months of maintenance in the laboratory.


Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1465
Author(s):  
Chao Shen ◽  
Liuyan Huang ◽  
Guangwu Xie ◽  
Yulai Wang ◽  
Zongkai Ma ◽  
...  

Increasing discharge of plastic debris into aquatic ecosystems and the worsening ecological risks have received growing attention. Once released, plastic debris could serve as a new substrate for microbes in waters. The complex relationship between plastics and biofilms has aroused great interest. To confirm the hypothesis that the presence of plastic in water affects the composition of biofilm in natural state, in situ biofilm culture experiments were conducted in a lake for 40 days. The diversity of biofilm attached on natural (cobble stones (CS) and wood) and plastic substrates (Polyethylene terephthalate (PET) and Polymethyl methacrylate (PMMA)) were compared, and the community structure and composition were also analyzed. Results from high-throughput sequencing of 16S rRNA showed that the diversity and species richness of biofilm bacterial communities on natural substrate (observed species of 1353~1945, Simpson index of 0.977~0.989 and Shannon–Wiener diversity index of 7.42~8.60) were much higher than those on plastic substrates (observed species of 900~1146, Simpson index of 0.914~0.975 and Shannon–Wiener diversity index of 5.47~6.99). The NMDS analyses were used to confirm the taxonomic significance between different samples, and Anosim (p = 0.001, R = 0.892) and Adonis (p = 0.001, R = 808, F = 11.19) demonstrated that this classification was statistically rigorous. Different dominant bacterial communities were found on plastic and natural substrates. Alphaproteobacterial, Betaproteobacteria and Synechococcophycideae dominated on the plastic substrate, while Gammaproteobacteria, Phycisphaerae and Planctomycetia played the main role on the natural substrates. The bacterial community structure of the two substrates also showed significant difference which is consistent with previous studies using other polymer types. Our results shed light on the fact that plastic debris can serve as a new habitat for biofilm colonization, unlike natural substrates, pathogens and plastic-degrading microorganisms selectively attached to plastic substrates, which affected the bacterial community structure and composition in aquatic environment. This study provided a new insight into understanding the potential impacts of plastics serving as a new habitat for microbial communities in freshwater environments. Future research should focus on the potential impacts of plastic-attached biofilms in various aquatic environments and the whole life cycle of plastics (i.e., from plastic fragments to microplastics) and also microbial flock characteristics using microbial plastics in the natural environment should also be addressed.


1999 ◽  
Vol 65 (4) ◽  
pp. 1721-1730 ◽  
Author(s):  
Allison E. McCaig ◽  
L. Anne Glover ◽  
James I. Prosser

ABSTRACT Bacterial community structure and diversity in rhizospheres in two types of grassland, distinguished by both plant species and fertilization regimen, were assessed by performing a 16S ribosomal DNA (rDNA) sequence analysis of DNAs extracted from triplicate soil plots. PCR products were cloned, and 45 to 48 clones from each of the six libraries were partially sequenced. Phylogenetic analysis of the resultant 275 clone sequences indicated that there was considerable variation in abundance in replicate unfertilized, unimproved soil samples and fertilized, improved soil samples but that there were no significant differences in the abundance of any phylogenetic group. Several clone sequences were identical in the 16S rDNA region analyzed, and the clones comprised eight pairs of duplicate clones and two sets of triplicate clones. Many clones were found to be most closely related to environmental clones obtained in other studies, although three clones were found to be identical to culturable species in databases. The clones were clustered into operational taxonomic units at a level of sequence similarity of >97% in order to quantify diversity. In all, 34 clusters containing two or more sequences were identified, and the largest group contained nine clones. A number of diversity, dominance, and evenness indices were calculated, and they all indicated that diversity was high, reflecting the low coverage of rDNA libraries achieved. Differences in diversity between sample types were not observed. Collector’s curves, however, indicated that there were differences in the underlying community structures; in particular, there was reduced diversity of organisms of the α subdivision of the class Proteobacteria (α-proteobacteria) in improved soils.


Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 701 ◽  
Author(s):  
Fengling Zhang ◽  
Xingjia Xiang ◽  
Yuanqiu Dong ◽  
Shaofei Yan ◽  
Yunwei Song ◽  
...  

Intestinal bacterial communities form an integral component of the organism. Many factors influence gut bacterial community composition and diversity, including diet, environment and seasonality. During seasonal migration, birds use many habitats and food resources, which may influence their intestinal bacterial community structure. Hooded crane (Grus monacha) is a migrant waterbird that traverses long distances and occupies varied habitats. In this study, we investigated the diversity and differences in intestinal bacterial communities of hooded cranes over the migratory seasons. Fecal samples from hooded cranes were collected at a stopover site in two seasons (spring and fall) in Lindian, China, and at a wintering ground in Shengjin Lake, China. We analyzed bacterial communities from the fecal samples using high throughput sequencing (Illumina Mi-seq). Firmicutes, Proteobacteria, Tenericutes, Cyanobacteria, and Actinobacteria were the dominant phyla across all samples. The intestinal bacterial alpha-diversity of hooded cranes in winter was significantly higher than in fall and spring. The bacterial community composition significantly differed across the three seasons (ANOSIM, P = 0.001), suggesting that seasonal fluctuations may regulate the gut bacterial community composition of migratory birds. This study provides baseline information on the seasonal dynamics of intestinal bacterial community structure in migratory hooded cranes.


2009 ◽  
Vol 8 (1) ◽  
pp. 147-157 ◽  
Author(s):  
Paula Arroyo ◽  
Gemma Ansola ◽  
Ivan Blanco ◽  
Patricia Molleda ◽  
Estanislao de Luis Calabuig ◽  
...  

This work provides information about bacterial community structure in natural wastewater treatment systems treating different types of wastewater. The diversity and composition of bacterial communities associated with the rhizosphere of Typha latifolia and Salix atrocinerea were studied and compared among two different natural wastewater treatment systems, using the direct sequencing of the 16S ribosomal RNA codifying genes. Phylogenetic affiliations of the bacteria detected allowed us to define the main groups present in these particular ecosystems. Moreover, bacterial community structure was studied through two diversity indices. Ten identified and five non-identified phyla were found in the samples; the phylum Proteobacteria was the predominant group in the four ecosystems. The results showed a bacterial community dominated by beta-proteobacteria and a lower diversity value in the swine wastewater treatment system. The municipal wastewater treatment system presented a high diverse community in both macrophytes (Typha latifolia and Salix atrocinerea), with gamma-proteobacteria and alpha-proteobacteria, respectively, as the most abundant groups.


2011 ◽  
Vol 343-344 ◽  
pp. 351-356
Author(s):  
Xia Jia ◽  
Chun Juan Zhou

The effect of long-term elevated CO2(as open top chambers) on rhizosphere and bulk bacterial community structure in Pinus sylvestriformis seedlings field was investigated in July, August, and September. The bacterial communities were processed by Denaturing Gradient Gel Electrophoresis (DGGE) analysis of bacterial 16S rDNA fragments amplified by PCR (Polymerase Chain Reaction) from DNA extracted directly from soil. DGGE profiles from rhizosphere samples showed large changes in rhizosphere bacterial community under elevated CO2compared to ambient except for that in September. For bulk samples, bacterial community structure changed when exposed to elevated CO2in three months. With the exception of bulk samples in August, a similitude of bacterial communities structures existed between different elevated CO2concentrations by analyzing UPGMA dendrogram based on Jaccard’s coefficient.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2367 ◽  
Author(s):  
Isabelle Laforest-Lapointe ◽  
Christian Messier ◽  
Steven W. Kembel

BackgroundThe diversity and composition of the microbial community of tree leaves (the phyllosphere) varies among trees and host species and along spatial, temporal, and environmental gradients. Phyllosphere community variation within the canopy of an individual tree exists but the importance of this variation relative to among-tree and among-species variation is poorly understood. Sampling techniques employed for phyllosphere studies include picking leaves from one canopy location to mixing randomly selected leaves from throughout the canopy. In this context, our goal was to characterize the relative importance of intra-individual variation in phyllosphere communities across multiple species, and compare this variation to inter-individual and interspecific variation of phyllosphere epiphytic bacterial communities in a natural temperate forest in Quebec, Canada.MethodsWe targeted five dominant temperate forest tree species including angiosperms and gymnosperms:Acer saccharum,Acer rubrum,Betula papyrifera,Abies balsameaandPicea glauca. For one randomly selected tree of each species, we sampled microbial communities at six distinct canopy locations: bottom-canopy (1–2 m height), the four cardinal points of mid-canopy (2–4 m height), and the top-canopy (4–6 m height). We also collected bottom-canopy leaves from five additional trees from each species.ResultsBased on an analysis of bacterial community structure measured via Illumina sequencing of the bacterial 16S gene, we demonstrate that 65% of the intra-individual variation in leaf bacterial community structure could be attributed to the effect of inter-individual and inter-specific differences while the effect of canopy location was not significant. In comparison, host species identity explains 47% of inter-individual and inter-specific variation in leaf bacterial community structure followed by individual identity (32%) and canopy location (6%).DiscussionOur results suggest that individual samples from consistent positions within the tree canopy from multiple individuals per species can be used to accurately quantify variation in phyllosphere bacterial community structure. However, the considerable amount of intra-individual variation within a tree canopy ask for a better understanding of how changes in leaf characteristics and local abiotic conditions drive spatial variation in the phyllosphere microbiome.


Author(s):  
Zufei Xiao ◽  
Beihong Zhang ◽  
Yangbao Wang ◽  
Zhinong Jin ◽  
Feng Li ◽  
...  

Abstract: Plant types and soil bacterial communities had a close relationship, understanding the profound association between them contributes to better learn bacterial ecological function for plant growth. In this study, rhizosphere soil of six different chemotype Cinnamomum camphora trees were collected, including C. bodinieri var. citralifera, [C. camphora (Linn.) Presl], camphora-type, cineole-type, linalool-type and isoborneol-type. Soil properties content and bacterial communities were analyzed. Two chemotype C. camphora, including [C. camphora (Linn.) Presl] and linalool-type, shaped similar bacterial community structure, decreased Firmcutes relative abundance. richness estimators (Chao1 index and Ace index) of [C. camphora (Linn.) Presl] were decreased compared with the others. Furthermore, soil bacterial community structure was also similar among bodinieri var. citralifera, camphora-type, cineole-type and isoborneol-type. Hence, different chemotype C. camphora altered soil nutrient and shaped rhizosphere bacterial communities.


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