scholarly journals Cellular life from the three domains and viruses are transcriptionally active in a hypersaline desert community

2019 ◽  
Author(s):  
Gherman Uritskiy ◽  
Michael J. Tisza ◽  
Diego R Gelsinger ◽  
Adam Munn ◽  
James Taylor ◽  
...  

SummaryMicrobial communities play essential roles in the biosphere and understanding the mechanisms underlying their functional adaptations to environmental conditions is critical for predicting their behavior. This aspect of microbiome function has not been well characterized in natural high-salt environments. To address this knowledge gap, and to build a general framework of relating the genomic and transcriptomic components in a microbiome, we performed a meta-omic survey of extremophile communities inhabiting halite (salt) nodules in the Atacama Desert. We found that the major phyla of this halophilic community have very different levels of total transcriptional activity and that different metabolic pathways were activated in their transcriptomes. We report that a novel Dolichomastix alga – the only eukaryote found in this system – was by far the most active community member. It produced the vast majority of the community’s photosynthetic transcripts despite being outnumbered by members of the Cyanobacteria. The divergence in the transcriptional landscapes of these segregated communities, compared to the relatively stable metagenomic functional potential, suggests that microbiomes in each salt nodule undergo unique transcriptional adjustments to adapt to local conditions. We also report the characterization of several previously unknown halophilic viruses, many of which exhibit transcriptional activity indicative of host infection.Originality-Significance StatementWhile the metagenomics of hypersaline environments have already led to many discoveries, the transcriptional adaptations and functions of halophilic microbial communities in natural environments remains understudied. We perform the first robust meta-omic investigation of a hypersaline desert ecosystem, linking the genomic and transcriptional elements of the community. Our analysis unexpectedly revealed that Eukaryotes may be the main primary producers in this extreme environment, despite halophilic Archaea and Bacteria dominating the biomass. We also expand on the existing known diversity of halophilic viruses and demonstrate abundance (copies per million reads) and metatranscriptomic activity (transcripts per million reads); putative hosts are shown on the right.

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2299
Author(s):  
Jéssica P. Silva ◽  
Alonso R. P. Ticona ◽  
Pedro R. V. Hamann ◽  
Betania F. Quirino ◽  
Eliane F. Noronha

Lignocellulosic residues are low-cost abundant feedstocks that can be used for industrial applications. However, their recalcitrance currently makes lignocellulose use limited. In natural environments, microbial communities can completely deconstruct lignocellulose by synergistic action of a set of enzymes and proteins. Microbial degradation of lignin by fungi, important lignin degraders in nature, has been intensively studied. More recently, bacteria have also been described as able to break down lignin, and to have a central role in recycling this plant polymer. Nevertheless, bacterial deconstruction of lignin has not been fully elucidated yet. Direct analysis of environmental samples using metagenomics, metatranscriptomics, and metaproteomics approaches is a powerful strategy to describe/discover enzymes, metabolic pathways, and microorganisms involved in lignin breakdown. Indeed, the use of these complementary techniques leads to a better understanding of the composition, function, and dynamics of microbial communities involved in lignin deconstruction. We focus on omics approaches and their contribution to the discovery of new enzymes and reactions that impact the development of lignin-based bioprocesses.


2021 ◽  
Vol 13 (8) ◽  
pp. 4293
Author(s):  
Yuqing Lin ◽  
Jingjing Wu ◽  
Yongqing Xiong

With the background of China’s new energy vehicles (NEVs) subsidies declining, there is an important practical significance to effectively play the role of the nonsubsidized consumption promotion mechanisms. The nonsubsidized mechanisms for NEVs are classified into two types—concept induction and policy incentives, and differences in the sensitivity of the two types of mechanisms on potential consumer purchase intentions due to differences in urban traffic patterns and consumer education levels are analyzed. The results show that consumers in cities with medium to high traffic pressure are more sensitive to the right-of-way privileges component of the policy incentives, and consumers in cities with low traffic pressure are more sensitive to the charging guarantee component of the policy incentives. Consumers with medium to high education are more sensitive to the pro-environmental component in concept induction, and consumers with low education are more sensitive to the charging guarantee policy component of the policy incentives. Therefore, the implementation of the nonsubsidized mechanisms for NEVs in China should adopt differentiated strategies based on local conditions and vary with each individual.


2019 ◽  
Author(s):  
Xiaochu Li ◽  
Floricel Gonzalez ◽  
Nathaniel Esteves ◽  
Birgit E. Scharf ◽  
Jing Chen

AbstractCoexistence of bacteriophages, or phages, and their host bacteria plays an important role in maintaining the microbial communities. In natural environments with limited nutrients, motile bacteria can actively migrate towards locations of richer resources. Although phages are not motile themselves, they can infect motile bacterial hosts and spread in space via the hosts. Therefore, in a migrating microbial community coexistence of bacteria and phages implies their co-propagation in space. Here, we combine an experimental approach and mathematical modeling to explore how phages and their motile host bacteria coexist and co-propagate. When lytic phages encountered motile host bacteria in our experimental set up, a sector-shaped lysis zone formed. Our mathematical model indicates that local nutrient depletion and the resulting inhibition of proliferation and motility of bacteria and phages are the key to formation of the observed lysis pattern. The model further reveals the straight radial boundaries in the lysis pattern as a tell-tale sign for coexistence and co-propagation of bacteria and phages. Emergence of such a pattern, albeit insensitive to extrinsic factors, requires a balance between intrinsic biological properties of phages and bacteria, which likely results from co-evolution of phages and bacteria.Author summaryCoexistence of phages and their bacterial hosts is important for maintaining the microbial communities. In a migrating microbial community, coexistence between phages and host bacteria implies that they co-propagate in space. Here we report a novel phage lysis pattern that is indicative of this co-propagation. The corresponding mathematical model we developed highlights a crucial dependence of the lysis pattern and implied phage-bacteria co-propagation on intrinsic properties allowing proliferation and spreading of the microbes in space. Remarkably, extrinsic factors, such as overall nutrient level, do not influence phage-bacteria coexistence and co-propagation. Findings from this work have strong implications for dispersal of phages mediated by motile bacterial communities, which will provide scientific basis for the fast-growing applications of phages.


2021 ◽  
Author(s):  
Shira Houwenhuyse ◽  
Lore Bulteel ◽  
Naina Goel ◽  
Isabel Vanoverberghe ◽  
Ellen Decaestecker

Studies on stressor responses are often performed in controlled laboratory settings. The microbial communities in laboratory setting often differ from the natural environment, which could ultimately be reflected in different stress responses. In this study, we investigated how stressor responses differed between laboratory and natural conditions in Daphnia magna when exposed to single or multiple stressors. Daphnia individuals were exposed to the toxic cyanobacterium Microcystis aeruginosa and a fungal infection, Aspergillus aculeatus like type. Three genotypes were included to investigate genotype-specific responses. Survival, reproduction and body size were monitored for three weeks and gut microbial communities were sampled and characterized at the end of the experiment. Our study shows that natural environments have a more diverse microbial community compared with laboratory conditions, which was ultimately reflected in the gut microbiomes after inoculation. Stressor responses in Daphnia were affected by their bacterial environment for survival, but not for fecundity and body size. Fecuntiy and body size did show a main stressor effect, which could possibly be linked with stessor-specific microbiomes (for Microcystis and the combined stressor treatment). In addition, genotype-specific responses were detected for survival and fecundity, which could be linked with the selective capabilities of the Daphnia genotypes to select beneficial or neutral microbial stains from the environment.


2021 ◽  
pp. 2631309X2110519
Author(s):  
Marcela Torres-Wong

For decades, Indigenous communities living in Mexico’s oil-producing state of Tabasco suffered violence, environmental contamination, and the destruction of their traditional livelihood. The administration of Andrés Manuel López Obrador (AMLO) taking office in 2018 promised to govern for the poorest people in Mexico, emphasizing the wellbeing of Indigenous peoples. However, as part of his nationalist agenda AMLO is pursuing aggressive exploitation of hydrocarbons upon the lead of state-owned company Pemex. This article argues that the Mexican government still denies Indigenous peoples living nearby oil reserves the right to self-determination. We examine this phenomenon through the Chontal community of Oxiacaque in the state of Tabasco suffering environmental contamination and health problems caused by the oil industry. We emphasize the government’s use of resource nationalism to legitimize violence against Indigenous communities and their natural environments. Further, the expansion of social programs and infrastructure building serves to obtain Indigenous compliance with the unsustainable fossil fuel industry.


2019 ◽  
Vol 9 (7) ◽  
pp. 1355
Author(s):  
Koji Ishiya ◽  
Sachiyo Aburatani

To understand the activities of complex microbial communities in various natural environments and living organisms, we need to capture the compositional changes in their taxonomic abundance. Here, we propose a new computational framework to detect compositional changes in microorganisms, including minor bacteria. This framework is designed to statistically assess relative variations in taxonomic abundance. By using this approach, we detected compositional changes in the human gut microbiome that might be associated with short-term human dietary changes. Our approach can shed light on the compositional changes of minor microorganisms that are easily overlooked.


1994 ◽  
Vol 8 (2) ◽  
pp. 218-229 ◽  
Author(s):  
John J. Accordino

This essay reviews recent evaluations of three of the most widely used state and local economic development strategies—traditional business recruitment, enterprise zones, and high-technology development. The studies do not succeed in their efforts to produce broadly generalizable findings that provide clear guidance to state and local policymakers and practitioners. Rather, they show that local conditions are responsible for the success or failure and level of net community benefits to be derived from any approach. Under the right conditions, each of the approaches described here might be appropriate.


A mathematical–physical model for erosion and deposition of sand is formulated and related to the logarithmic hyperbolic distributional form of mass–size distributions. The location-scale invariant parameters χ and ξ of the hyperbolic distribution express, respectively, the skewness and the kurtosis of that distribution, and the triangular domain of variation of these two parameters is referred to as the hyperbolic shape triangle. The erosion–deposition model implies that erosion will tend to move the ( χ , ξ)-position of a given sediment to the right-hand part of the shape triangle and that deposition will move the ( χ , ξ)-position towards the left part of the triangle, along specified curves. This is confirmed by sediments from a variety of natural environments. An empirically determined curve bisecting the shape triangle is found to separate the samples from predominantly depositional environments as compared with the samples from predominantly erosional environments. The hyperbolic shape triangle is also found to discriminate well between samples of different but closely related origins.


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