scholarly journals Comparison of the Microbial Community Structures of Untreated Wastewaters from Different Geographic Locales

2013 ◽  
Vol 79 (9) ◽  
pp. 2906-2913 ◽  
Author(s):  
Orin C. Shanks ◽  
Ryan J. Newton ◽  
Catherine A. Kelty ◽  
Susan M. Huse ◽  
Mitchell L. Sogin ◽  
...  

ABSTRACTMicrobial sewage communities consist of a combination of human fecal microorganisms and nonfecal microorganisms, which may be residents of urban sewer infrastructure or flowthrough originating from gray water or rainwater inputs. Together, these different microorganism sources form an identifiable community structure that may serve as a signature for sewage discharges and as candidates for alternative indicators specific for human fecal pollution. However, the structure and variability of this community across geographic space remains uncharacterized. We used massively parallel 454 pyrosequencing of the V6 region in 16S rRNA genes to profile microbial communities from 13 untreated sewage influent samples collected from a wide range of geographic locations in the United States. We obtained a total of 380,175 high-quality sequences for sequence-based clustering, taxonomic analyses, and profile comparisons. The sewage profile included a discernible core human fecal signature made up of several abundant taxonomic groups withinFirmicutes,Bacteroidetes,Actinobacteria, andProteobacteria. DNA sequences were also classified into fecal, sewage infrastructure (i.e., nonfecal), and transient groups based on data comparisons with fecal samples. Across all sewage samples, an estimated 12.1% of sequences were fecal in origin, while 81.4% were consistently associated with the sewage infrastructure. The composition of feces-derived operational taxonomic units remained congruent across all sewage samples regardless of geographic locale; however, the sewage infrastructure community composition varied among cities, with city latitude best explaining this variation. Together, these results suggest that untreated sewage microbial communities harbor a core group of fecal bacteria across geographically dispersed wastewater sewage lines and that ambient water quality indicators targeting these select core microorganisms may perform well across the United States.

2017 ◽  
Vol 83 (16) ◽  
Author(s):  
Daniel S. Jones ◽  
Kim A. Lapakko ◽  
Zachary J. Wenz ◽  
Michael C. Olson ◽  
Elizabeth W. Roepke ◽  
...  

ABSTRACT The Duluth Complex in northeastern Minnesota hosts economically significant deposits of copper, nickel, and platinum group elements (PGEs). The primary sulfide mineralogy of these deposits includes the minerals pyrrhotite, chalcopyrite, pentlandite, and cubanite, and weathering experiments show that most sulfide-bearing rock from the Duluth Complex generates moderately acidic leachate (pH 4 to 6). Microorganisms are important catalysts for metal sulfide oxidation and could influence the quality of water from mines in the Duluth Complex. Nevertheless, compared with that of extremely acidic environments, much less is known about the microbial ecology of moderately acidic sulfide-bearing mine waste, and so existing information may have little relevance to those microorganisms catalyzing oxidation reactions in the Duluth Complex. Here, we characterized the microbial communities in decade-long weathering experiments (kinetic tests) conducted on crushed rock and tailings from the Duluth Complex. Analyses of 16S rRNA genes and transcripts showed that differences among microbial communities correspond to pH, rock type, and experimental treatment. Moreover, microbial communities from the weathered Duluth Complex rock were dominated by taxa that are not typically associated with acidic mine waste. The most abundant operational taxonomic units (OTUs) were from the genera Meiothermus and Sulfuriferula, as well as from diverse clades of uncultivated Chloroflexi, Acidobacteria, and Betaproteobacteria. Specific taxa, including putative sulfur-oxidizing Sulfuriferula spp., appeared to be primarily associated with Duluth Complex rock, but not pyrite-bearing rocks subjected to the same experimental treatment. We discuss the implications of these results for the microbial ecology of moderately acidic mine waste with low sulfide content, as well as for kinetic testing of mine waste. IMPORTANCE Economic sulfide mineral deposits in the Duluth Complex may represent the largest undeveloped source of copper and nickel on Earth. Microorganisms are important catalysts for sulfide mineral oxidation, and research on extreme acidophiles has improved our ability to manage and remediate mine wastes. We found that the microbial assemblages associated with weathered rock from the Duluth Complex are dominated by organisms not widely associated with mine waste or mining-impacted environments, and we describe geochemical and experimental influences on community composition. This report will be a useful foundation for understanding the microbial biogeochemistry of moderately acidic mine waste from these and similar deposits.


mBio ◽  
2019 ◽  
Vol 10 (5) ◽  
Author(s):  
Tess E. Brewer ◽  
Emma L. Aronson ◽  
Keshav Arogyaswamy ◽  
Sharon A. Billings ◽  
Jon K. Botthoff ◽  
...  

ABSTRACT While most bacterial and archaeal taxa living in surface soils remain undescribed, this problem is exacerbated in deeper soils, owing to the unique oligotrophic conditions found in the subsurface. Additionally, previous studies of soil microbiomes have focused almost exclusively on surface soils, even though the microbes living in deeper soils also play critical roles in a wide range of biogeochemical processes. We examined soils collected from 20 distinct profiles across the United States to characterize the bacterial and archaeal communities that live in subsurface soils and to determine whether there are consistent changes in soil microbial communities with depth across a wide range of soil and environmental conditions. We found that bacterial and archaeal diversity generally decreased with depth, as did the degree of similarity of microbial communities to those found in surface horizons. We observed five phyla that consistently increased in relative abundance with depth across our soil profiles: Chloroflexi, Nitrospirae, Euryarchaeota, and candidate phyla GAL15 and Dormibacteraeota (formerly AD3). Leveraging the unusually high abundance of Dormibacteraeota at depth, we assembled genomes representative of this candidate phylum and identified traits that are likely to be beneficial in low-nutrient environments, including the synthesis and storage of carbohydrates, the potential to use carbon monoxide (CO) as a supplemental energy source, and the ability to form spores. Together these attributes likely allow members of the candidate phylum Dormibacteraeota to flourish in deeper soils and provide insight into the survival and growth strategies employed by the microbes that thrive in oligotrophic soil environments. IMPORTANCE Soil profiles are rarely homogeneous. Resource availability and microbial abundances typically decrease with soil depth, but microbes found in deeper horizons are still important components of terrestrial ecosystems. By studying 20 soil profiles across the United States, we documented consistent changes in soil bacterial and archaeal communities with depth. Deeper soils harbored communities distinct from those of the more commonly studied surface horizons. Most notably, we found that the candidate phylum Dormibacteraeota (formerly AD3) was often dominant in subsurface soils, and we used genomes from uncultivated members of this group to identify why these taxa are able to thrive in such resource-limited environments. Simply digging deeper into soil can reveal a surprising number of novel microbes with unique adaptations to oligotrophic subsurface conditions.


Subject Post-Obama armed UAV policy. Significance As President Barack Obama prepares to leave office in January 2017, his administration has called for the United States to lead development of a set of international norms to govern the use of armed UAVs ('unmanned aerial vehicles' or 'drones'). The international proliferation and military use of armed UAVs by nations outside the circle of trusted US allies have highlighted the urgency of formulating clearly articulated international rules to govern an otherwise vaguely defined arena of international behaviour dominated by US precedent. Impacts Congressional aversion to supporting ground interventions abroad will enable the next president further to delay UAV policy reform. A wide range of countries frustrated with restrictions from Washington may turn to China as a key supplier of armed UAVs. Failed US efforts to reform the covert drone programme may complicate intelligence-sharing with European allies.


Subject Regulation of gene-edited organisms. Significance The European Court of Justice (ECJ) last month ruled that new processes for altering the genetic structure of organisms should be subject to existing EU legislation on genetically modified organisms (GMOs). The move calls into question whether European researchers and businesses will be able to participate in the global race to exploit the rapidly evolving technology of gene editing. Impacts Innovation in gene editing will usher in a wide range of new crops in the United States and emerging economies over the next decade. This will further enhance the position of GM products in global agriculture (particularly for staples such as soybean, cotton and maize). The EU is unlikely to apply trade restrictions upon such products.


2017 ◽  
Vol 83 (11) ◽  
Author(s):  
Ryan A. Blaustein ◽  
Graciela L. Lorca ◽  
Julie L. Meyer ◽  
Claudio F. Gonzalez ◽  
Max Teplitski

ABSTRACTStable associations between plants and microbes are critical to promoting host health and productivity. The objective of this work was to test the hypothesis that restructuring of the core microbiota may be associated with the progression of huanglongbing (HLB), the devastating citrus disease caused byLiberibacter asiaticus,Liberibacter americanus, andLiberibacter africanus. The microbial communities of leaves (n= 94) and roots (n= 79) from citrus trees that varied by HLB symptom severity, cultivar, location, and season/time were characterized with Illumina sequencing of 16S rRNA genes. The taxonomically rich communities contained abundant core members (i.e., detected in at least 95% of the respective leaf or root samples), some overrepresented site-specific members, and a diverse community of low-abundance variable taxa. The composition and diversity of the leaf and root microbiota were strongly associated with HLB symptom severity and location; there was also an association with host cultivar. The relative abundance ofLiberibacterspp. among leaf microbiota positively correlated with HLB symptom severity and negatively correlated with alpha diversity, suggesting that community diversity decreases as symptoms progress. Network analysis of the microbial community time series identified a mutually exclusive relationship betweenLiberibacterspp. and members of theBurkholderiaceae,Micromonosporaceae, andXanthomonadaceae. This work confirmed several previously described plant disease-associated bacteria, as well as identified new potential implications for biological control. Our findings advance the understanding of (i) plant microbiota selection across multiple variables and (ii) changes in (core) community structure that may be a precondition to disease establishment and/or may be associated with symptom progression.IMPORTANCEThis study provides a comprehensive overview of the core microbial community within the microbiomes of plant hosts that vary in extent of disease symptom progression. With 16S Illumina sequencing analyses, we not only confirmed previously described bacterial associations with plant health (e.g., potentially beneficial bacteria) but also identified new associations and potential interactions between certain bacteria and an economically important phytopathogen. The importance of core taxa within broader plant-associated microbial communities is discussed.


mBio ◽  
2012 ◽  
Vol 3 (4) ◽  
Author(s):  
Scott D. Kobayashi ◽  
James M. Musser ◽  
Frank R. DeLeo

ABSTRACT Staphylococcus aureus is a human commensal bacterium and a prominent cause of infections globally. The high incidence of S. aureus infections is compounded by the ability of the microbe to readily acquire resistance to antibiotics. In the United States, methicillin-resistant S. aureus (MRSA) is a leading cause of morbidity and mortality by a single infectious agent. Therapeutic options for severe MRSA infections are limited to a few antibiotics to which the organism is typically susceptible, including vancomycin. Acquisition of high-level vancomycin resistance by MRSA is a major concern, but to date, there have been only 12 vancomycin-resistant S. aureus (VRSA) isolates reported in the United States and all belong to a phylogenetic lineage known as clonal complex 5. To gain enhanced understanding of the genetic characteristics conducive to the acquisition of vancomycin resistance by S. aureus , V. N. Kos et al. performed whole-genome sequencing of all 12 VRSA isolates and compared the DNA sequences to the genomes of other S. aureus strains. The findings provide new information about the evolutionary history of VRSA and identify genetic features that may bear on the relationship between S. aureus clonal complex 5 strains and the acquisition of vancomycin resistance genes from enterococci.


2018 ◽  
Vol 84 (18) ◽  
Author(s):  
Claudia Leong ◽  
Jillian J. Haszard ◽  
Blair Lawley ◽  
Anna Otal ◽  
Rachael W. Taylor ◽  
...  

ABSTRACT The introduction of “solids” (i.e., complementary foods) to the milk-only diet in early infancy affects the development of the gut microbiota. The aim of this study was to determine whether a “baby-led” approach to complementary feeding that encourages the early introduction of an adult-type diet results in alterations of the gut microbiota composition compared to traditional spoon-feeding. The Baby-Led Introduction to SolidS (BLISS) study randomized 206 infants to BLISS (a modified version of baby-led weaning [BLW], the introduction of solids at 6 months of age, followed by self-feeding of family foods) or control (traditional spoon-feeding of purées) groups. Fecal microbiotas and 3-day weighed-diet records were analyzed for a subset of 74 infants at 7 and 12 months of age. The composition of the microbiota was determined by sequencing of 16S rRNA genes amplified by PCR from bulk DNA extracted from feces. Diet records were used to estimate food and dietary fiber intake. Alpha diversity (number of operational taxonomic units [OTUs]) was significantly lower in BLISS infants at 12 months of age (difference [95% confidence interval {CI}] of 31 OTUs [3.4 to 58.5]; P = 0.028), and while there were no significant differences between control and BLISS infants in relative abundances of Bifidobacteriaceae, Enterobacteriaceae, Veillonellaceae, Bacteroidaceae, Erysipelotrichaceae, Lachnospiraceae, or Ruminococcaceae at 7 or 12 months of age, OTUs representing the genus Roseburia were less prevalent in BLISS microbiotas at 12 months. Mediation models demonstrated that the intake of “fruit and vegetables” and “dietary fiber” explained 29% and 25%, respectively, of the relationship between group (BLISS versus control) and alpha diversity. IMPORTANCE The introduction of solid foods (complementary feeding or weaning) to infants leads to more-complex compositions of microbial communities (microbiota or microbiome) in the gut. In baby-led weaning (BLW), infants are given only finger foods that they can pick up and feed themselves—there is no parental spoon-feeding of puréed baby foods—and infants are encouraged to eat family meals. BLW is a new approach to infant feeding that is increasing in popularity in the United States, New Zealand, the United Kingdom, and Canada. We used mediation modeling, commonly used in health research but not in microbiota studies until now, to identify particular dietary components that affected the development of the infant gut microbiota.


2015 ◽  
Vol 81 (13) ◽  
pp. 4246-4252 ◽  
Author(s):  
Yan Yan ◽  
Eiko E. Kuramae ◽  
Peter G. L. Klinkhamer ◽  
Johannes A. van Veen

ABSTRACTIt is hard to assess experimentally the importance of microbial diversity in soil for the functioning of terrestrial ecosystems. An approach that is often used to make such assessment is the so-called dilution method. This method is based on the assumption that the biodiversity of the microbial community is reduced after dilution of a soil suspension and that the reduced diversity persists after incubation of more or less diluted inocula in soil. However, little is known about how the communities develop in soil after inoculation. In this study, serial dilutions of a soil suspension were made and reinoculated into the original soil previously sterilized by gamma irradiation. We determined the structure of the microbial communities in the suspensions and in the inoculated soils using 454-pyrosequencing of 16S rRNA genes. Upon dilution, several diversity indices showed that, indeed, the diversity of the bacterial communities in the suspensions decreased dramatically, withProteobacteriaas the dominant phylum of bacteria detected in all dilutions. The structure of the microbial community was changed considerably in soil, withProteobacteria,Bacteroidetes, andVerrucomicrobiaas the dominant groups in most diluted samples, indicating the importance of soil-related mechanisms operating in the assembly of the communities. We found unique operational taxonomic units (OTUs) even in the highest dilution in both the suspensions and the incubated soil samples. We conclude that the dilution approach reduces the diversity of microbial communities in soil samples but that it does not allow accurate predictions of the community assemblage during incubation of (diluted) suspensions in soil.


2012 ◽  
Vol 78 (17) ◽  
pp. 5983-5993 ◽  
Author(s):  
Hyo Jung Lee ◽  
Ji Young Jung ◽  
Young Kyoon Oh ◽  
Sang-Suk Lee ◽  
Eugene L. Madsen ◽  
...  

ABSTRACTPyrosequencing of 16S rRNA genes (targetingBacteriaandArchaea) and1H nuclear magnetic resonance were applied to investigate the rumen microbiota and metabolites of Hanwoo steers in the growth stage (HGS), Hanwoo steers in the late fattening stage (HFS), Holstein-Friesian dairy cattle (HDC), and Korean native goats (KNG) in the late fattening stage. This was a two-part investigation. We began by comparing metabolites and microbiota of Hanwoo steers at two stages of husbandry. Statistical comparisons of metabolites and microbial communities showed no significant differences between HFS and HGS (differing by a dietary shift at 24 months and age [67 months versus 12 months]). We then augmented the study by extending the investigation to HDC and KNG. Overall, pyrosequencing of 16S rRNA genes showed that the rumens had highly diverse microbial communities containing many previously undescribed microorganisms. Bioinformatic analysis revealed that the bacterial sequences were predominantly affiliated with four phyla—Bacteroidetes,Firmicutes,Fibrobacteres, andProteobacteria—in all ruminants. However, interestingly, the bacterial reads belonging toFibrobactereswere present at a very low abundance (<0.1%) in KNG. Archaeal community analysis showed that almost all of these reads fell into a clade related to, but distinct from, known cultivated methanogens. Statistical analyses showed that the microbial communities and metabolites of KNG were clearly distinct from those of other ruminants. In addition, bacterial communities and metabolite profiles of HGS and HDC, fed similar diets, were distinctive. Our data indicate that bovine host breeds override diet as the key factor that determines bacterial community and metabolite profiles in the rumen.


2017 ◽  
Vol 83 (21) ◽  
Author(s):  
Cecilia M. Chiriac ◽  
Edina Szekeres ◽  
Knut Rudi ◽  
Andreea Baricz ◽  
Adriana Hegedus ◽  
...  

ABSTRACT This report describes the biodiversity and ecology of microbial mats developed in thermal gradients (20 to 65°C) in the surroundings of three drillings (Chiraleu [CH], Ciocaia [CI], and Mihai Bravu [MB]) tapping a hyperthermal aquifer in Romania. Using a metabarcoding approach, 16S rRNA genes were sequenced from both DNA and RNA transcripts (cDNA) and compared. The relationships between the microbial diversity and the physicochemical factors were explored. Additionally, the cDNA data were used for in silico functionality predictions, bringing new insights into the functional potential and dynamics of these communities. The results showed that each hot spring determined the formation of distinct microbial communities. In the CH mats (40 to 53°C), the abundance of Cyanobacteria decreased with temperature, opposite to those of Chloroflexi and Proteobacteria. Ectothiorhodospira, Oscillatoria, and methanogenic archaea dominated the CI communities (20 to 65°C), while the MB microbial mats (53 to 65°C) were mainly composed of Chloroflexi, Hydrogenophilus, Thermi, and Aquificae. Alpha-diversity was negatively correlated with the increase in water temperature, while beta-diversity was shaped in each hot spring by the unique combination of physicochemical parameters, regardless of the type of nucleic acid analyzed (DNA versus cDNA). The rank correlation analysis revealed a unique model that associated environmental data with community composition, consisting in the combined effect of Na+, K+, HCO3 −, and PO4 3− concentrations, together with temperature and electrical conductivity. These factors seem to determine the grouping of samples according to location, rather than with the similarities in thermal regimes, showing that other parameters beside temperature are significant drivers of biodiversity. IMPORTANCE Hot spring microbial mats represent a remarkable manifestation of life on Earth and have been intensively studied for decades. Moreover, as hot spring areas are isolated and have a limited exchange of organisms, nutrients, and energy with the surrounding environments, hot spring microbial communities can be used in model studies to elucidate the colonizing potential within extreme settings. Thus, they are of great importance in evolutionary biology, microbial ecology, and exobiology. In spite of all the efforts that have been made, the current understanding of the influence of temperature and water chemistry on the microbial community composition, diversity, and abundance in microbial mats is limited. In this study, the composition and diversity of microbial communities developed in thermal gradients in the vicinity of three hot springs from Romania were investigated, each having particular physicochemical characteristics. Our results expose new factors that could determine the formation of these ecosystems, expanding the current knowledge in this regard.


Sign in / Sign up

Export Citation Format

Share Document