scholarly journals Diversity of NC10 Bacteria and ANME-2d Archaea in Sediments of Fault Zones at Lake Baikal

Diversity ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 10
Author(s):  
Anna Lomakina ◽  
Tatyana Pogodaeva ◽  
Gennady Kalmychkov ◽  
Svetlana Chernitsyna ◽  
Tamara Zemskaya

Anaerobic oxidation of methane (AOM) reduces methane emissions from marine ecosystems, but we know little about AOM in freshwater reservoirs. Lake Baikal is the world’s only freshwater reservoir where gas hydrates (GH) are found. Despite that AOM has been demonstrated in deep sediments of Lake Baikal did not reveal methane-oxidizing archaea ANME1, 2, or 3, which are responsible for AOM in marine sediments. A search for representatives Candidatus Methylomirabilis oxyfera (M. oxyfera)-like bacteria (NC10) and Candidatus Methanoperedens nitroreducens (M. nitroreducens)-like archaea (ANME-2d) has been carried out in the different types of Lake Baikal methane enriched sediments. We used different molecular biology methods including high-throughput sequencing and PCR analysis, using 16S rRNA genes as well as different functional genes of AOM (mcrA and pmoA). We found diverse M. oxyfera-like bacteria and M. nitroreducens-like archaea in various geological structures in Lake Baikal (methane seep and mud volcano), which were different from the composition of the discharged fluid. We also considered possible electron acceptors for this process in the sediments of Lake Baikal.

2011 ◽  
Vol 77 (19) ◽  
pp. 6780-6787 ◽  
Author(s):  
B. R. Briggs ◽  
J. W. Pohlman ◽  
M. Torres ◽  
M. Riedel ◽  
E. L. Brodie ◽  
...  

ABSTRACTMethane release from seafloor sediments is moderated, in part, by the anaerobic oxidation of methane (AOM) performed by consortia of archaea and bacteria. These consortia occur as isolated cells and aggregates within the sulfate-methane transition (SMT) of diffusion and seep-dominant environments. Here we report on a new SMT setting where the AOM consortium occurs as macroscopic pink to orange biofilms within subseafloor fractures. Biofilm samples recovered from the Indian and northeast Pacific Oceans had a cellular abundance of 107to 108cells cm−3. This cell density is 2 to 3 orders of magnitude greater than that in the surrounding sediments. Sequencing of bacterial 16S rRNA genes indicated that the bacterial component is dominated byDeltaproteobacteria, candidate division WS3, andChloroflexi, representing 46%, 15%, and 10% of clones, respectively. In addition, major archaeal taxa found in the biofilm were related to the ANME-1 clade,Thermoplasmatales, andDesulfurococcales, representing 73%, 11%, and 10% of archaeal clones, respectively. The sequences of all major taxa were similar to sequences previously reported from cold seep environments. PhyloChip microarray analysis detected all bacterial phyla identified by the clone library plus an additional 44 phyla. However, sequencing detected more archaea than the PhyloChip within the phyla ofMethanosarcinalesandDesulfurococcales. The stable carbon isotope composition of the biofilm from the SMT (−35 to −43‰) suggests that the production of the biofilm is associated with AOM. These biofilms are a novel, but apparently widespread, aggregation of cells represented by the ANME-1 clade that occur in methane-rich marine sediments.


2020 ◽  
Vol 96 (3) ◽  
Author(s):  
Lijun Bao ◽  
Likun Gu ◽  
Bo Sun ◽  
Wenyang Cai ◽  
Shiwei Zhang ◽  
...  

ABSTRACT Phyllosphere harbors diverse microorganisms, which influence plant growth and health. In order to understand the extent to which environmental factors affect epiphytic microbial communities, we characterized microbial communities on leaves of three separate tree species present on the college campus, and also present within a forest park over two seasons. Quantitative PCR analysis showed the quantity of 16S rRNA genes was lower in May compared with October, while the abundances of functional genes (nifH and bacterial amoA genes) were extremely high in May. High-throughput sequencing revealed a large variation in the diversity and composition of bacterial and diazotrophic communities over the two seasons, and showed the abundance of functional genera, such as Nocardioides, Bacillus and Zoogloea were significantly elevated in May. In addition, xenobiotic biodegradation pathways of bacterial communities were clearly elevated in May. Network analysis showed the correlations between phyllospheric bacteria in May were more complex than that in October and showed greater negative correlations. These results were consistent in all tree species in this study. This study showed that phyllospheric bacteria varied greatly in different seasons, which implies that different growing seasons should be considered in the exploitation of the interactions between phyllospheric microorganisms and host plants.


2010 ◽  
Vol 7 (4) ◽  
pp. 5463-5496
Author(s):  
M. Beck ◽  
T. Riedel ◽  
J. Graue ◽  
J. Köster ◽  
N. Kowalski ◽  
...  

Abstract. To date, North Sea tidal flat sediments have been intensively studied down to a depth of 5 m below sea floor (mbsf). However, little is known about the biogeochemistry, microbial abundance, and activity of sulfate reducers as well of methanogens in deeper layers. For this study, we hypothesized that the imprint of the paleo-environment is reflected in current microbiogeochemical processes. Therefore, 20 m-long cores were retrieved from the tidal-flat area of Spiekeroog Island, NW Germany. Two drill sites were selected with a close distance of only 900 meters, but where sedimentation occurred under different environmental conditions: first, a paleo-channel filled with Holocene sediments and second, a mainly Pleistocene sedimentary succession. In general, the numbers of bacterial 16S rRNA genes are one to two orders of magnitude higher than those of Archaea. The abundances of key genes for sulfate reduction and methanogenesis (dsrA and mcrA) correspond to the sulfate and methane profiles. A co-variance of these key genes at sulfate-methane interfaces and enhanced potential AOM rates suggest that anaerobic oxidation of methane may occur in these layers. Microbial and biogeochemical profiles are vertically stretched relative to 5 m-deep cores from shallower sediments in the same study area. Compared to the deep marine environment, the profiles are transitional between the shallow subsurface and the marine deep biosphere. Our interdisciplinary analysis shows that the microbial abundances and metabolic rates are elevated in the Holocene compared to Pleistocene sediments. However, this is mainly due to present environmental conditions such as pore water flow and organic matter availability. The paleo-environmental imprint is still visible but superimposed by these processes.


2011 ◽  
Vol 8 (1) ◽  
pp. 55-68 ◽  
Author(s):  
M. Beck ◽  
T. Riedel ◽  
J. Graue ◽  
J. Köster ◽  
N. Kowalski ◽  
...  

Abstract. To date, North Sea tidal-flat sediments have been intensively studied down to a depth of 5 m below seafloor (mbsf). However, little is known about the biogeochemistry, microbial abundance, and activity of sulfate reducers as well as methanogens in deeper layers. In this study, two 20 m-long cores were retrieved from the tidal-flat area of Spiekeroog Island, NW Germany. The drill sites were selected with a close distance of 900 m allowing to compare two depositional settings: first, a paleo-channel filled with Holocene sediments and second, a mainly Pleistocene sedimentary succession. Analyzing these cores, we wanted to test to which degree the paleo-environmental imprint is superimposed by present processes. In general, the numbers of bacterial 16S rRNA genes are one to two orders of magnitude higher than those of Archaea. The abundances of key genes for sulfate reduction and methanogenesis (dsrA and mcrA) correspond to the sulfate and methane profiles. A co-variance of these key genes at sulfate-methane interfaces and enhanced ex situ AOM rates suggest that anaerobic oxidation of methane may occur in these layers. Microbial and biogeochemical profiles are vertically stretched relative to 5 m-deep cores from shallower sediments in the same study area, but still appear compressed compared to deep sea sediments. Our interdisciplinary analysis shows that the microbial abundances and metabolic rates are elevated in the Holocene compared to Pleistocene sediments. However, this is mainly due to present environmental conditions such as pore water flow and organic matter availability. The paleo-environmental imprint is still visible but superimposed by these processes.


2007 ◽  
Vol 73 (20) ◽  
pp. 6669-6677 ◽  
Author(s):  
Eric S. Boyd ◽  
Robert A. Jackson ◽  
Gem Encarnacion ◽  
James A. Zahn ◽  
Trevor Beard ◽  
...  

ABSTRACT Elemental sulfur (S0) is associated with many geochemically diverse hot springs, yet little is known about the phylogeny, physiology, and ecology of the organisms involved in its cycling. Here we report the isolation, characterization, and ecology of two novel, S0-reducing Crenarchaea from an acid geothermal spring referred to as Dragon Spring. Isolate 18U65 grows optimally at 70 to 72°C and at pH 2.5 to 3.0, while isolate 18D70 grows optimally at 81°C and pH 3.0. Both isolates are chemoorganotrophs, dependent on complex peptide-containing carbon sources, S0, and anaerobic conditions for respiration-dependent growth. Glycerol dialkyl glycerol tetraethers (GDGTs) containing four to six cyclopentyl rings were present in the lipid fraction of isolates 18U65 and 18D70. Physiological characterization suggests that the isolates are adapted to the physicochemical conditions of Dragon Spring and can utilize the natural organic matter in the spring as a carbon and energy source. Quantitative PCR analysis of 16S rRNA genes associated with the S0 flocs recovered from several acid geothermal springs using isolate-specific primers indicates that these two populations together represent 17 to 37% of the floc-associated DNA. The physiological characteristics of isolates 18U65 and 18D70 are consistent with their potential widespread distribution and putative role in the cycling of sulfur in acid geothermal springs throughout the Yellowstone National Park geothermal complex. Based on phenotypic and genetic characterization, the designations Caldisphaera draconis sp. nov. and Acidilobus sulfurireducens sp. nov. are proposed for isolates 18U65 and 18D70, respectively.


2021 ◽  
Vol 8 ◽  
Author(s):  
Wenxia Wang ◽  
Songlin Huang ◽  
Liangliang Yang ◽  
Guogang Zhang

There are many and diverse intestinal microbiota, and they are closely related to various physiological functions of the body. They directly participate in the host's food digestion, nutrient absorption, energy metabolism, immune response, and many other physiological activities and are also related to the occurrence of many diseases. The intestinal microbiota are extremely important for maintaining normal physical health. In order to explore the composition and differences of the intestinal microbiota of whooper swans in different wintering areas, we collected fecal samples of whooper swans in Sanmenxia, Henan, and Rongcheng, Shandong, and we used the Illumina HiSeq platform to perform high-throughput sequencing of bacterial 16S rRNA genes. Comparison between Sanmenxia and Rongcheng showed no significant differences in ACE, Chao 1, Simpson, and Shannon indices (p > 0.05). Beta diversity results showed significant differences in bacterial communities between two groups [analysis of similarity (ANOSIM): R = 0.80, p = 0.011]. Linear discriminant analysis effect size (LEfSe) analysis showed that at the phylum level, the relative abundance of Actinobacteria was significantly higher in Sanmenxia whooper swans than Rongcheng whooper swans. At the genus level, the amount of Psychrobacter and Carnobacterium in Sanmenxia was significantly higher in Rongcheng, while the relative abundance Catellicoccus and Lactobacillus was significantly higher in Rongcheng than in Sanmenxia. This study analyzed the composition, characteristics, and differences of the intestinal microbiota of the whooper swans in different wintering environments and provided theoretical support for further exploring the relationship between the intestinal microbiota of the whooper swans and the external environment. And it played an important role in the overwintering physiology and ecology, population management, and epidemic prevention and control of whooper swans.


2017 ◽  
Vol 61 ◽  
pp. 69-84 ◽  
Author(s):  
Ali Naghoni ◽  
Giti Emtiazi ◽  
Mohammad Ali Amoozegar ◽  
Zahra Etemadifar ◽  
Seyed Abolhassan Shahzadeh Fazeli

Repetitive extragenic palindromic elements-polymerase chain reaction (rep-PCR) with 16S ribosomal ribonucleic acid (16S rRNA) genes sequences successfully used for the analysis of microbial community. In this study, the prokaryotic community in Lake Meyghan described by using rep-PCR analysis along with 16S rRNA gene sequencing. The water samples were collected from Lake Meyghan in November 2013. All samples were diluted and cultured on three different media. To estimate the number of prokaryotes per milliliter of the lake we used quantitative real‑time PCR (qPCR). Rep-PCR combination with 16S rRNA gene sequencing was performed to investigate prokaryotes biodiversity in the lake. 305 strains were isolated in this work; 113 isolates for green region, 102 isolates for red region, and 90 isolates for white region. The dendrograms generated 10, 7, and 9 clusters for a 70 % similarity cut-off for green, red, and white regions, respectively. Based on rep-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by (77.5 %)Halobacteriacaeand many isolates were related to the generaHalorubrum,Haloarcula,Haloterrigena,Natrinema, andHalovivaxin the white region. In the red region more isolated strains (57.5 %) belonged toBacillaceaeand the remaining 42.5 % of isolates belonged to archaea domain,Halorubrum, andHaloarcula. In the green region members ofGammaproteobacteriawere recoverd, this region was dominant withPseudoalteromonas,Salinivibrio, andAliidiomarina.


Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 645
Author(s):  
Junlie Zhou ◽  
Mengran Du ◽  
Jiwei Li ◽  
Hengchao Xu ◽  
Kaiwen Ta ◽  
...  

Phosphorus (P) is an important nutrient for biological communities in cold seeps. However, our knowledge on the source, species, and cycling of P in cold seep environments is limited. In this study, the concentration, species, and micro to nanometer scale distribution of P in seep carbonates were examined at three deep-sea cold seeps in the South China Sea and East China Sea. The Ca-P accounts for the largest proportion of P—followed by detrital-P, Fe-P, organic-P, and exchangeable-P. The distribution patterns of Ca-P, detrital-P, and organic-P in the seep carbonates differ from one another, as shown by elemental mapping with NanoSIMS and scanning electron microscopy. The covariation of P with Ca and C reveals that Ca-P co-precipitates with Ca-carbonate, which is linked to the process of sulfate-driven anaerobic oxidation of methane. Organic-P is also observed within biofilm-like organic carbon aggregates, revealing the microbial enrichment of P by fluids in the process of anaerobic oxidation of methane. P with a granulated morphology was identified as detrital-P derived from deep sediments. Most importantly, it is evident that Ca-P is positively correlated to the Fe content in all the seep carbonates. This indicates the likelihood that the dissolved P in cold-seep fluids is released primarily from Fe oxides through Fe-driven anaerobic oxidation of methane in deep sediments. These processes associated with different species of P may have significant implications for P geochemical cycling and anaerobic oxidation of methane impelled by Fe and sulfate reduction in cold seep environments.


2019 ◽  
Vol 7 (2) ◽  
pp. 35 ◽  
Author(s):  
Joseph Hakim ◽  
Julie Schram ◽  
Aaron Galloway ◽  
Casey Morrow ◽  
Michael Crowley ◽  
...  

The sea urchin Strongylocentrotus purpuratus (order Camarodonta, family Strongylocentrotidae) can be found dominating low intertidal pool biomass on the southern coast of Oregon, USA. In this case study, three adult sea urchins were collected from their shared intertidal pool, and the bacteriome of their pharynx, gut tissue, and gut digesta, including their tide pool water and algae, was determined using targeted high-throughput sequencing (HTS) of the 16S rRNA genes and bioinformatics tools. Overall, the gut tissue demonstrated Arcobacter and Sulfurimonas (Epsilonproteobacteria) to be abundant, whereas the gut digesta was dominated by Psychromonas (Gammaproteobacteria), Propionigenium (Fusobacteria), and Flavobacteriales (Bacteroidetes). Alpha and beta diversity analyses indicated low species richness and distinct microbial communities comprising the gut tissue and digesta, while the pharynx tissue had higher richness, more closely resembling the water microbiota. Predicted functional profiles showed Kyoto Encyclopedia of Genes and Genomes (KEGG) Level-2 categories of energy metabolism, membrane transport, cell motility, and signal transduction in the gut tissue, and the gut digesta represented amino acid, carbohydrate, vitamin and cofactor metabolisms, and replication and repair. Co-occurrence network analysis showed the potential relationships and key taxa, such as the highly abundant Arcobacter and Propionigenium, influencing population patterns and taxonomic organization between the gut tissue and digesta. These results demonstrate a trend of microbial community integration, allocation, predicted metabolic roles, and taxonomic co-occurrence patterns in the S. purpuratus gut ecosystem.


2019 ◽  
Vol 47 (10) ◽  
pp. 5037-5047
Author(s):  
Chen Yun ◽  
Li Zhiyan ◽  
Zhao Chong ◽  
Liu Jing ◽  
Zhang Xin ◽  
...  

Objective To analyze the pathogenic community diversity of dental caries patients from Tu, Hui, Tibetan, and Han Chinese ethnic groups. Methods Forty saliva samples were collected from the following patients with dental caries: Tu from Huzhu County (n = 10), Hui from Ping’an County (n = 10), Han from Xining city (n = 10), and Tibetan from Yushu (n = 10). High-throughput sequencing of bacterial 16S rRNA genes (V3-V4) was performed using the Illumina MiSeq sequencing platform. Results Based on 97% similarity clustering, operational taxonomic units of Tu, Hui, Tibetan, and Han ethnic groups were 181, 210, 38, and 67, respectively. In Tu patients, 11 phyla, 19 classes, and 89 genera were identified, compared with 13 phyla, 21 classes, and 113 genera in Hui patients, two phyla, four classes, and 21 genera in Tibetan patients, five phyla, nine classes, and 34 genera in Han patients, and four phyla, five classes, and 12 genera from the control group. The main pathogens of dental caries included Veillonella, Aggregatibacter, Leptotrichia, Bacteroides, Granulicatella, Streptococcus, and Prevotella. Conclusion The pathogenic microorganisms of dental caries differ greatly among Tu, Hui, Tibetan, and Han ethnic groups. These findings provide a theoretical basis for the effective prevention and treatment of dental caries in different Chinese populations.


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