Polychlorinated biphenyl (PCB) anaerobic degradation in marine sediments: microcosm study and role of autochthonous microbial communities

Abstract Background The intestinal microbiota plays a crucial role in protecting the host from pathogenic microbes, modulating immunity and regulating metabolic processes. We studied the simplified human intestinal microbiota (SIHUMIx) consisting of eight bacterial species with a particular focus on the discovery of novel small proteins with less than 100 amino acids (= sProteins), some of which may contribute to shape the simplified human intestinal microbiota. Although sProteins carry out a wide range of important functions, they are still often missed in genome annotations, and little is known about their structure and function in individual microbes and especially in microbial communities. Results We created a multi-species integrated proteogenomics search database (iPtgxDB) to enable a comprehensive identification of novel sProteins. Six of the eight SIHUMIx species, for which no complete genomes were available, were sequenced and de novo assembled. Several proteomics approaches including two earlier optimized sProtein enrichment strategies were applied to specifically increase the chances for novel sProtein discovery. The search of tandem mass spectrometry (MS/MS) data against the multi-species iPtgxDB enabled the identification of 31 novel sProteins, of which the expression of 30 was supported by metatranscriptomics data. Using synthetic peptides, we were able to validate the expression of 25 novel sProteins. The comparison of sProtein expression in each single strain versus a multi-species community cultivation showed that six of these sProteins were only identified in the SIHUMIx community indicating a potentially important role of sProteins in the organization of microbial communities. Two of these novel sProteins have a potential antimicrobial function. Metabolic modelling revealed that a third sProtein is located in a genomic region encoding several enzymes relevant for the community metabolism within SIHUMIx. Conclusions We outline an integrated experimental and bioinformatics workflow for the discovery of novel sProteins in a simplified intestinal model system that can be generically applied to other microbial communities. The further analysis of novel sProteins uniquely expressed in the SIHUMIx multi-species community is expected to enable new insights into the role of sProteins on the functionality of bacterial communities such as those of the human intestinal tract.

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The microbial world in a changing environment

Revista chilena de historia natural ◽

10.1186/s40693-021-00099-y ◽

2021 ◽

Vol 94 (1) ◽

Author(s):

Rafael Vicuña ◽

Bernardo González

Keyword(s):

Climate Change ◽

Microbial Communities ◽

Recent Literature ◽

Public Awareness ◽

Complete Evaluation ◽

Microbial World ◽

Sustainable Environment ◽

Entire Planet ◽

New Strategies

Abstract Background In this article we would like to touch on the key role played by the microbiota in the maintenance of a sustainable environment in the entire planet. For obvious reasons, this article does not intend to review thoroughly this extremely complex topic, but rather to focus on the main threats that this natural scenario is presently facing. Methods Recent literature survey. Results Despite the relevance of microorganisms have in our planet, the effects of climate change on microbial communities have been scarcely and not systematically addressed in literature. Although the role of microorganisms in emissions of greenhouse gases has received some attention, there are several microbial processes that are affected by climate change with consequences that are presently under assessment. Among them, host-pathogen interactions, the microbiome of built environment, or relations among plants and beneficial microbes. Conclusions Further research is required to advance in knowledge of the effect of climate change on microbial communities. One of the main targets should be a complete evaluation of the global microbial functional diversity and the design of new strategies to cope with limitations in methods to grow microorganisms in the laboratory. These efforts should contribute to raise a general public awareness on the major role played by the microbiota on the various Earth ecosystems.

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Role of microbial communities on organic removal during petrochemical wastewater biological treatment with pure oxygen aeration

Journal of Water Process Engineering ◽

10.1016/j.jwpe.2021.102151 ◽

2021 ◽

Vol 42 ◽

pp. 102151

Author(s):

Dong Wang ◽

Dongxu Sun ◽

Xiao Tian ◽

Nannan Liu ◽

Chenchen Wang ◽

...

Keyword(s):

Microbial Communities ◽

Biological Treatment ◽

Pure Oxygen ◽

Petrochemical Wastewater ◽

Organic Removal ◽

Wastewater Biological Treatment

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Prenatal exposure to persistent organic pollutants as a risk factor of offspring metabolic syndrome development during childhood

Reviews on Environmental Health ◽

10.1515/reveh-2020-0113 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Marlene Cervantes González

Keyword(s):

Metabolic Syndrome ◽

Organic Pollutants ◽

Prenatal Exposure ◽

Persistent Organic Pollutants ◽

Animal Studies ◽

Polychlorinated Biphenyl ◽

Environmental Pollutants ◽

Epidemiological Studies ◽

Experimental Findings

Abstract Persistent Organic Pollutants (POPs) are exogenous, artificially made chemicals that can disrupt the biological system of individuals and animals. POPs encompass a variety of chemicals including, dioxins, organochlorines (OCs), polychlorinated biphenyl (PCBs), and perfluoroalkyl substances (PFASs) that contain a long half-life and highly resistant to biodegradation. These environmental pollutants accumulate over time in adipose tissues of living organisms and alter various insulin function-related genes. Childhood Metabolic Syndrome (MetS) consists of multiple cardiovascular risk factors, insulin function being one of them. Over the years, the incidence of the syndrome has increased dramatically. It is imperative to explore the role of persistent organic pollutants in the development of Childhood Metabolic Syndrome. Some epidemiological studies have reported an association between prenatal exposure to POPs and offspring MetS development throughout childhood. These findings have been replicated in animal studies in which these pollutants exercise negative health outcomes such as obesity and increased waist circumference. This review discusses the role of prenatal exposure to POPs among offspring who develop MetS in childhood, the latest research on the MetS concept, epidemiological and experimental findings on MetS, and the POPs modes of action. This literature review identified consistent research results on this topic. Even though the studies in this review had many strengths, one major weakness was the usage of different combinations of MetS criteria to measure the outcomes. These findings elucidate the urgent need to solidify the pediatric MetS definition. An accurate definition will permit scientists to measure the MetS as a health outcome properly and allow clinicians to diagnose pediatric MetS and provide individualized treatment appropriately.

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Anaerobic Degradation Pathway of Linear Alkylbenzene Sulfonates (LAS) in Sulfate-Reducing Marine Sediments

Environmental Science & Technology ◽

10.1021/es9032887 ◽

2010 ◽

Vol 44 (5) ◽

pp. 1670-1676 ◽

Cited By ~ 42

Author(s):

Pablo A. Lara-Martín ◽

Abelardo Gómez-Parra ◽

José Luis Sanz ◽

Eduardo González-Mazo

Keyword(s):

Marine Sediments ◽

Anaerobic Degradation ◽

Degradation Pathway ◽

Linear Alkylbenzene ◽

Sulfate Reducing ◽

Linear Alkylbenzene Sulfonates

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The role of tephra in enhancing organic carbon preservation in marine sediments

Earth-Science Reviews ◽

10.1016/j.earscirev.2019.03.018 ◽

2019 ◽

Vol 192 ◽

pp. 480-490 ◽

Cited By ~ 8

Author(s):

Jack Longman ◽

Martin R. Palmer ◽

Thomas M. Gernon ◽

Hayley R. Manners

Keyword(s):

Organic Carbon ◽

Marine Sediments

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Deterministic Selection Dominates Microbial Community Assembly in Termite Mounds Across a Large Spatial Area

10.21203/rs.3.rs-34782/v1 ◽

2020 ◽

Author(s):

Qing-Lin Chen ◽

Hang-Wei Hu ◽

Zhen-Zhen Yan ◽

Chao-Yu Li ◽

Bao-Anh Thi Nguyen ◽

...

Keyword(s):

Microbial Community ◽

Stochastic Processes ◽

Microbial Communities ◽

Fungal Community ◽

Community Assembly ◽

Distance Decay ◽

Termite Mounds ◽

Deterministic Processes ◽

Microbial Community Assembly

Abstract Background: Termites are ubiquitous insects in tropical and subtropical habitats, where they construct massive mounds from soil, their saliva and excreta. Termite mounds harbor an enormous amount of microbial inhabitants, which regulate multiple ecosystem functions such as mitigating methane emissions and increasing ecosystem resistance to climate change. However, we lack a mechanistic understanding about the role of termite mounds in modulating the microbial community assembly processes, which are essential to unravel the biological interactions of soil fauna and microorganisms, the major components of soil food webs. We conducted a large-scale survey across a >1500 km transect in northern Australia to investigate biogeographical patterns of bacterial and fungal community in 134 termite mounds and the relative importance of deterministic versus stochastic processes in microbial community assembly. Results: Microbial alpha (number of phylotypes) and beta (changes in bacterial and fungal community composition) significantly differed between termite mounds and surrounding soils. Microbial communities in termite mounds exhibited a significant distance-decay pattern, and fungal communities had a stronger distance-decay relationship (slope = -1.91) than bacteria (slope = -0.21). Based on the neutral community model (fitness < 0.7) and normalized stochasticity ratio index (NST) with a value below the 50% boundary point, deterministic selection, rather than stochastic forces, predominated the microbial community assembly in termite mounds. Deterministic processes exhibited significantly weaker impacts on bacteria (NST = 45.23%) than on fungi (NST = 33.72%), probably due to the wider habitat niche breadth and higher potential migration rate of bacteria. The abundance of antibiotic resistance genes (ARGs) was negatively correlated with bacterial/fungal biomass ratios, indicating that ARG content might be an important biotic factor that drove the biogeographic pattern of microbial communities in termite mounds. Conclusions: Deterministic processes play a more important role than stochastic processes in shaping the microbial community assembly in termite mounds, an unique habitat ubiquitously distributed in tropical and subtropical ecosystems. An improved understanding of the biogeographic patterns of microorganisms in termite mounds is crucial to decipher the role of soil faunal activities in shaping microbial community assembly, with implications for their mediated ecosystems functions and services.

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