scholarly journals Alkalo-Thermophilic Microbial Diversity of the Tecozautla Geyser, México

Author(s):  
Jesus Alberto Segovia-Cruz ◽  
Valeria Souza ◽  
Yuridia Mercado-Flores ◽  
Miguel Angel Anducho-Reyes ◽  
Genaro Vargas-Hernández ◽  
...  

Abstract Microbial mats have been studied in many thermal systems; the most iconic is Yellowstone. In Mexico, the information on microbial mats is scarce and therefore novel. In this research, the thermophilic microbial composition of samples from four areas of the Tecozautla geyser, Hidalgo, Mexico, was studied: sediments (GD), salt deposits (GA), and microbial mats (GB and GC). The samples were taken at the outlet of the geyser (94 °C) and in storage pools with temperatures of 61.5-65 °C. Sequencing of the 16S rRNA gene amplicons was carried out, obtaining 1,425,506 readings, and was analyzed through the Quantitative Insights Into Microbial Ecology software package version 2 (qiime2). 32 phyla were identified in the four samples being the most representative for the GA sample: Armatimonadetes, Chloroflexi, Cyanobacteria, and Thermi, with abundances of 46.35, 19.18, 3.27, and 1.82 %, respectively. For the GB sample, they were Proteobacteria, Bacteroidetes, Cyanobacteria, Spirochaetes, Thermi, and Firmicutes with abundances of 25.23, 22.04, 20.42, 12.31, 4.56, and 1.32 %, respectively. For the GC sample, abundances of 55.60, 9.85, 7.04, 7.01, and 6.15 % were observed for the phylum Chloroflexi, Armatimonadetes, Proteobacteria, Cyanobacteria, and Acidobacteria, respectively. Finally, for the GD sample, the most abundant phyla were Chloroflexi (36.10 %), Cyanobacteria (17.13 %), Armatimonadetes (15.59 %), Proteobacteria (5.45 %), and Nitrospirae with (3.21 %). The metabolic functionality of the microbial communities present in the samples was inferred using the 16S rRNA amplicons. This work represents the first report of the microbial communities present in the Tecozautla geyser.

2019 ◽  
Vol 7 (9) ◽  
pp. 357 ◽  
Author(s):  
Moonsuk Hur ◽  
Soo-Je Park

Heavy metal pollution is a serious environmental problem as it adversely affects crop production and human activity. In addition, the microbial community structure and composition are altered in heavy-metal-contaminated soils. In this study, using full-length 16S rRNA gene sequences obtained by a PacBio RS II system, we determined the microbial diversity and community structure in heavy-metal-contaminated soil. Furthermore, we investigated the microbial distribution, inferred their putative functional traits, and analyzed the environmental effects on the microbial compositions. The soil samples selected in this study were heavily and continuously contaminated with various heavy metals due to closed mines. We found that certain microorganisms (e.g., sulfur or iron oxidizers) play an important role in the biogeochemical cycle. Using phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis, we predicted Kyoto Encyclopedia of Genes and Genomes (KEGG) functional categories from abundances of microbial communities and revealed a high proportion belonging to transport, energy metabolism, and xenobiotic degradation in the studied sites. In addition, through full-length analysis, Conexibacter-like sequences, commonly identified by environmental metagenomics among the rare biosphere, were detected. In addition to microbial composition, we confirmed that environmental factors, including heavy metals, affect the microbial communities. Unexpectedly, among these environmental parameters, electrical conductivity (EC) might have more importance than other factors in a community description analysis.


2016 ◽  
Author(s):  
Tatsuhiko Hoshino ◽  
Fumio Inagaki

AbstractNext-generation sequencing (NGS) is a powerful tool for analyzing environmental DNA and provides the comprehensive molecular view of microbial communities. For obtaining the copy number of particular sequences in the NGS library, however, additional quantitative analysis as quantitative PCR (qPCR) or digital PCR (dPCR) is required. Furthermore, number of sequences in a sequence library does not always reflect the original copy number of a target gene because of biases caused by PCR amplification, making it difficult to convert the proportion of particular sequences in the NGS library to the copy number using the mass of input DNA. To address this issue, we applied stochastic labeling approach with random-tag sequences and developed a NGS-based quantification protocol, which enables simultaneous sequencing and quantification of the targeted DNA. This quantitative sequencing (qSeq) is initiated from single-primer extension (SPE) using a primer with random tag adjacent to the 5’ end of target-specific sequence. During SPE, each DNA molecule is stochastically labeled with the random tag. Subsequently, first-round PCR is conducted, specifically targeting the SPE product, followed by second-round PCR to index for NGS. The number of random tags is only determined during the SPE step and is therefore not affected by the two rounds of PCR that may introduce amplification biases. In the case of 16S rRNA genes, after NGS sequencing and taxonomic classification, the absolute number of target phylotypes 16S rRNA gene can be estimated by Poisson statistics by counting random tags incorporated at the end of sequence. To test the feasibility of this approach, the 16S rRNA gene of Sulfolobus tokodaii was subjected to qSeq, which resulted in accurate quantification of 5.0 × 103to 5.0 × 104copies of the 16S rRNA gene. Furthermore, qSeq was applied to mock microbial communities and environmental samples, and the results were comparable to those obtained using digital PCR and relative abundance based on a standard sequence library. We demonstrated that the qSeq protocol proposed here is advantageous for providing less-biased absolute copy numbers of each target DNA with NGS sequencing at one time. By this new experiment scheme in microbial ecology, microbial community compositions can be explored in more quantitative manner, thus expanding our knowledge of microbial ecosystems in natural environments.


2019 ◽  
Author(s):  
Philipp Rausch ◽  
Malte Rühlemann ◽  
Britt Hermes ◽  
Shauni Doms ◽  
Tal Dagan ◽  
...  

AbstractBackgroundThe interplay between hosts and their associated microbiome is now recognized as a fundamental basis of the ecology, evolution and development of both players. These interdependencies inspired a new view of multicellular organisms as “metaorganisms”. The goal of the Collaborative Research Center “Origin and Function of Metaorganisms” is to understand why and how microbial communities form long-term associations with hosts from diverse taxonomic groups, ranging from sponges to humans in addition to plants.MethodsIn order to optimize the choice of analysis procedures, which may differ according to the host organism and question at hand, we systematically compared the two main technical approaches for profiling microbial communities, 16S rRNA gene amplicon- and metagenomic shotgun sequencing across our panel of ten host taxa. This includes two commonly used 16S rRNA gene regions and two amplification procedures, thus totaling five different microbial profiles per host sample.ConclusionWhile 16S rRNA gene-based analyses are subject to much skepticism, we demonstrate that many aspects of bacterial community characterization are consistent across methods and that metagenomic shotgun results are largely dependent on the employed pipeline. The resulting insight facilitates the selection of appropriate methods across a wide range of host taxa. Finally, by contrasting taxonomic and functional profiles and performing phylogenetic analysis, we provide important and novel insight into broad evolutionary patterns among metaorganisms, whereby the transition of animals from an aquatic to a terrestrial habitat marks a major event in the evolution of host-associated microbial composition.


Microbiome ◽  
2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Philipp Rausch ◽  
Malte Rühlemann ◽  
Britt M. Hermes ◽  
Shauni Doms ◽  
Tal Dagan ◽  
...  

Abstract Background The interplay between hosts and their associated microbiome is now recognized as a fundamental basis of the ecology, evolution, and development of both players. These interdependencies inspired a new view of multicellular organisms as “metaorganisms.” The goal of the Collaborative Research Center “Origin and Function of Metaorganisms” is to understand why and how microbial communities form long-term associations with hosts from diverse taxonomic groups, ranging from sponges to humans in addition to plants. Methods In order to optimize the choice of analysis procedures, which may differ according to the host organism and question at hand, we systematically compared the two main technical approaches for profiling microbial communities, 16S rRNA gene amplicon and metagenomic shotgun sequencing across our panel of ten host taxa. This includes two commonly used 16S rRNA gene regions and two amplification procedures, thus totaling five different microbial profiles per host sample. Conclusion While 16S rRNA gene-based analyses are subject to much skepticism, we demonstrate that many aspects of bacterial community characterization are consistent across methods. The resulting insight facilitates the selection of appropriate methods across a wide range of host taxa. Overall, we recommend single- over multi-step amplification procedures, and although exceptions and trade-offs exist, the V3 V4 over the V1 V2 region of the 16S rRNA gene. Finally, by contrasting taxonomic and functional profiles and performing phylogenetic analysis, we provide important and novel insight into broad evolutionary patterns among metaorganisms, whereby the transition of animals from an aquatic to a terrestrial habitat marks a major event in the evolution of host-associated microbial composition.


2020 ◽  
Author(s):  
Sesilje Weiss ◽  
David Taggart ◽  
Ian Smith ◽  
Kristopher M Helgen ◽  
Raphael Eisenhofer

Abstract Background: Marsupials are born much earlier than placental mammals, with most crawling from the birth canal to the protective marsupium (pouch) to further their development. However, little is known about the microbiology of the pouch and how it changes throughout a marsupial’s reproductive cycle. Here, using stringent controls, we characterized the microbial composition of multiple body sites from 26 wild Southern Hairy-nosed Wombats (SHNWs), including pouch samples from animals at different reproductive stages. Results: Using qPCR of the 16S rRNA gene we found higher concentrations of microbial DNA in the pouch than in negative controls. We observed significant differences in microbial composition and diversity between the body sites tested, as well as between pouch samples from different reproductive stages. Three of the five most abundant taxa identified in reproductively active pouches had closest matches to microbes previously isolated from tammar wallaby pouches. Conclusions: Our results suggest that SHNW pouches contain communities of microorganisms that are altered by the host reproductive cycle. We recommend further investigation into the roles that pouch microorganisms may play in marsupial reproductive health and joey survival.


2019 ◽  
Vol 37 (4_suppl) ◽  
pp. 489-489
Author(s):  
Dong Ho Lee ◽  
Mijin Seol ◽  
Yu Ra Lee ◽  
Young Soo Park ◽  
Cheol Min Shin ◽  
...  

489 Background: Dysbiosis of intestinal microbiota is promoting the development of colorectal cancer (CRC). We confirmed the intestinal microbiota composition from fecal sample of Korean CRC patients. Metagenomic analysis was performed and we isolated single microbes through culture-based method. Methods: CRC fecal samples were collected from 12 individuals. Metagenome Sequencing was based on the 16S rRNA gene amplicon on the Illumina MiSeq platform. The bacteria strains were subcultivated on the agar plate medium in aerobic and anaerobic and further identified by using the 16s rRNA gene sequencing. Results: Bacteria diversity by metagenome analysis was decreased in CRC group compared to control group. In CRC group, relative abundance of Firmicutes and Bacteroidetes were increased while the prevalence of Proteobacteria was decreased. The difference of microbial composition between control and CRC group was found at the genus level. Bacteroides, Parabacteroides of Bacteroidetes have increased and Acinetobacter, Pseudomonas of Proteobacteria have significantly decreased in CRC compared to control group. Using culture method, we isolated diverse bacteria of species level including five strains of Bacteroides; B. ovatus, B. uniformis, B. salyersiae, B. vulgatus and B. xylanisolvens and two strains of Fusobacterium; F. gonidiaformans and F. necrophorum from CRC patients. Conclusions: Metagenome analysis showed the genus Bacteroides, Parabacteroides of the phylum Bacteroidetes has increased and the genus Acinetobacter, Pseudomonas of Proteobacteria decreased in CRC group compared to control group. In addition to, we have isolated various strains associated with CRC by culture-based method.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Sesilje Weiss ◽  
David Taggart ◽  
Ian Smith ◽  
Kristofer M. Helgen ◽  
Raphael Eisenhofer

Abstract Background Marsupials are born much earlier than placental mammals, with most crawling from the birth canal to the protective marsupium (pouch) to further their development. However, little is known about the microbiology of the pouch and how it changes throughout a marsupial’s reproductive cycle. Here, using stringent controls, we characterized the microbial composition of multiple body sites from 26 wild Southern Hairy-nosed Wombats (SHNWs), including pouch samples from animals at different reproductive stages. Results Using qPCR of the 16S rRNA gene we detected a microbial community in the SHNW pouch. We observed significant differences in microbial composition and diversity between the body sites tested, as well as between pouch samples from different reproductive stages. The pouches of reproductively active females had drastically lower microbial diversity (mean ASV richness 19 ± 8) compared to reproductively inactive females (mean ASV richness 941 ± 393) and were dominated by gram positive bacteria from the Actinobacteriota phylum (81.7–90.6%), with the dominant families classified as Brevibacteriaceae, Corynebacteriaceae, Microbacteriaceae, and Dietziaceae. Three of the five most abundant sequences identified in reproductively active pouches had closest matches to microbes previously isolated from tammar wallaby pouches. Conclusions This study represents the first contamination-controlled investigation into the marsupial pouch microbiota, and sets a rigorous framework for future pouch microbiota studies. Our results indicate that SHNW pouches contain communities of microorganisms that are substantially altered by the host reproductive cycle. We recommend further investigation into the roles that pouch microorganisms may play in marsupial reproductive health and joey survival.


2014 ◽  
Vol 64 (Pt_3) ◽  
pp. 781-786 ◽  
Author(s):  
Maximo Sánchez ◽  
Martha-Helena Ramírez-Bahena ◽  
Alvaro Peix ◽  
María J. Lorite ◽  
Juan Sanjuán ◽  
...  

Strain S658T was isolated from a Lotus corniculatus nodule in a soil sample obtained in Uruguay. Phylogenetic analysis of the 16S rRNA gene and atpD gene showed that this strain clustered within the genus Phyllobacterium . The closest related species was, in both cases, Phyllobacterium trifolii PETP02T with 99.8 % sequence similarity in the 16S rRNA gene and 96.1 % in the atpD gene. The 16S rRNA gene contains an insert at the beginning of the sequence that has no similarities with other inserts present in the same gene in described rhizobial species. Ubiquinone Q-10 was the only quinone detected. Strain S658T differed from its closest relatives through its growth in diverse culture conditions and in the assimilation of several carbon sources. It was not able to reproduce nodules in Lotus corniculatus. The results of DNA–DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain should be classified as a representative of a novel species of the genus Phyllobacterium , for which the name Phyllobacterium loti sp. nov. is proposed. The type strain is S658T( = LMG 27289T = CECT 8230T).


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