scholarly journals Virus-mediated archaeal hecatomb in the deep seafloor

2016 ◽  
Vol 2 (10) ◽  
pp. e1600492 ◽  
Author(s):  
Roberto Danovaro ◽  
Antonio Dell’Anno ◽  
Cinzia Corinaldesi ◽  
Eugenio Rastelli ◽  
Ricardo Cavicchioli ◽  
...  
Keyword(s):  
Viral Infection ◽  
Deep Sea ◽  
Viral Infections ◽  
Biogeochemical Cycles ◽  
Global Scale ◽  
Viral Lysis ◽  
Group I ◽  
Global Biogeochemical Cycles ◽  
Bacterial Genes ◽  
The Impact

Viruses are the most abundant biological entities in the world’s oceans, and they play a crucial role in global biogeochemical cycles. In deep-sea ecosystems, archaea and bacteria drive major nutrient cycles, and viruses are largely responsible for their mortality, thereby exerting important controls on microbial dynamics. However, the relative impact of viruses on archaea compared to bacteria is unknown, limiting our understanding of the factors controlling the functioning of marine systems at a global scale. We evaluate the selectivity of viral infections by using several independent approaches, including an innovative molecular method based on the quantification of archaeal versus bacterial genes released by viral lysis. We provide evidence that, in all oceanic surface sediments (from 1000- to 10,000-m water depth), the impact of viral infection is higher on archaea than on bacteria. We also found that, within deep-sea benthic archaea, the impact of viruses was mainly directed at members of specific clades of Marine Group I Thaumarchaeota. Although archaea represent, on average, ~12% of the total cell abundance in the top 50 cm of sediment, virus-induced lysis of archaea accounts for up to one-third of the total microbial biomass killed, resulting in the release of ~0.3 to 0.5 gigatons of carbon per year globally. Our results indicate that viral infection represents a key mechanism controlling the turnover of archaea in surface deep-sea sediments. We conclude that interactions between archaea and their viruses might play a profound, previously underestimated role in the functioning of deep-sea ecosystems and in global biogeochemical cycles.

scholarly journals Macroecological drivers of archaea and bacteria in benthic deep-sea ecosystems

2016 ◽  
Vol 2 (4) ◽  
pp. e1500961 ◽  
Author(s):  
Roberto Danovaro ◽  
Massimiliano Molari ◽  
Cinzia Corinaldesi ◽  
Antonio Dell’Anno
Keyword(s):  
Climate Change ◽  
Field Study ◽  
Food Supply ◽  
Deep Sea ◽  
Crucial Role ◽  
Biogeochemical Cycles ◽  
High Latitudes ◽  
Group I ◽  
Extensive Field ◽  
Global Biogeochemical Cycles

Bacteria and archaea dominate the biomass of benthic deep-sea ecosystems at all latitudes, playing a crucial role in global biogeochemical cycles, but their macroscale patterns and macroecological drivers are still largely unknown. We show the results of the most extensive field study conducted so far to investigate patterns and drivers of the distribution and structure of benthic prokaryote assemblages from 228 samples collected at latitudes comprising 34°N to 79°N, and from ca. 400- to 5570-m depth. We provide evidence that, in deep-sea ecosystems, benthic bacterial and archaeal abundances significantly increase from middle to high latitudes, with patterns more pronounced for archaea, and particularly for Marine Group I Thaumarchaeota. Our results also reveal that different microbial components show varying sensitivities to changes in temperature conditions and food supply. We conclude that climate change will primarily affect deep-sea benthic archaea, with important consequences on global biogeochemical cycles, particularly at high latitudes.

scholarly journals Respiratory Viral Infection Alters the Gut Microbiota by Inducing Inappetence

mBio ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Helen T. Groves ◽  
Sophie L. Higham ◽  
Miriam F. Moffatt ◽  
Michael J. Cox ◽  
John S. Tregoning
Keyword(s):  
Weight Loss ◽  
Gut Microbiota ◽  
Viral Infection ◽  
Gut Microbiome ◽  
Viral Infections ◽  
Lung Infection ◽  
Significant Shift ◽  
Rsv Infection ◽  
Respiratory Viral Infections ◽  
The Impact

ABSTRACT Respiratory viral infections are extremely common, but their impacts on the composition and function of the gut microbiota are poorly understood. We previously observed a significant change in the gut microbiota after viral lung infection. Here, we show that weight loss during respiratory syncytial virus (RSV) or influenza virus infection was due to decreased food consumption, and that the fasting of mice altered gut microbiota composition independently of infection. While the acute phase tumor necrosis factor alpha (TNF-α) response drove early weight loss and inappetence during RSV infection, this was not sufficient to induce changes in the gut microbiota. However, the depletion of CD8+ cells increased food intake and prevented weight loss, resulting in a reversal of the gut microbiota changes normally observed during RSV infection. Viral infection also led to changes in the fecal gut metabolome, with a significant shift in lipid metabolism. Sphingolipids, polyunsaturated fatty acids (PUFAs), and the short-chain fatty acid (SCFA) valerate were all increased in abundance in the fecal metabolome following RSV infection. Whether this and the impact of infection-induced anorexia on the gut microbiota are part of a protective anti-inflammatory response during respiratory viral infections remains to be determined. IMPORTANCE The gut microbiota has an important role in health and disease: gut bacteria can generate metabolites that alter the function of immune cells systemically. Understanding the factors that can lead to changes in the gut microbiome may help to inform therapeutic interventions. This is the first study to systematically dissect the pathway of events from viral lung infection to changes in gut microbiota. We show that the cellular immune response to viral lung infection induces inappetence, which in turn alters the gut microbiome and metabolome. Strikingly, there was an increase in lipids that have been associated with the resolution of disease. This opens up new paths of investigation: first, what is the (presumably secreted) factor made by the T cells that can induce inappetence? Second, is inappetence an adaptation that accelerates recovery from infection, and if so, does the microbiome play a role in this?

scholarly journals Respiratory viral infection alters the gut microbiota by inducing inappetence

2019 ◽  
Author(s):  
Helen T. Groves ◽  
Sophie L. Higham ◽  
Miriam F. Moffatt ◽  
Michael J. Cox ◽  
John S. Tregoning
Keyword(s):  
Weight Loss ◽  
Gut Microbiota ◽  
Viral Infection ◽  
Unsaturated Fatty Acids ◽  
Viral Infections ◽  
Influenza Virus Infection ◽  
Significant Shift ◽  
Rsv Infection ◽  
Respiratory Viral Infections ◽  
The Impact

AbstractThe gut microbiota has an important role in health and disease. Respiratory viral infections are extremely common but their impact on the composition and function of the gut microbiota is poorly understood. We previously observed a significant change in the gut microbiota after viral lung infection. Here we show that weight loss during Respiratory Syncytial Virus (RSV) or influenza virus infection was due to decreased food consumption, and that fasting mice independently of infection altered gut microbiota composition. While the acute phase TNF-α response drove early weight loss and inappetence during RSV infection, this was not sufficient to induce changes in the gut microbiota. However, depleting CD8+ cells increased food intake and prevented weight loss resulting in a reversal of the gut microbiota changes normally observed during RSV infection. Viral infection also led to changes in the faecal gut metabolome during RSV infection, with a significant shift in lipid metabolism. Sphingolipids, poly-unsaturated fatty acids (PUFAs) and the short-chain fatty acid (SCFA) valerate all increased in abundance in the faecal metabolome following RSV infection. Whether this, and the impact of infection-induced anorexia on the gut microbiota, are part of a protective, anti-inflammatory response during respiratory viral infections remains to be determined.

scholarly journals Bioturbation enhances the aerobic respiration of lake sediments in warming lakes

2016 ◽  
Vol 12 (8) ◽  
pp. 20160448 ◽  
Author(s):  
Viktor Baranov ◽  
Jörg Lewandowski ◽  
Stefan Krause
Keyword(s):  
Lake Sediment ◽  
Carbon Metabolism ◽  
Seasonal Changes ◽  
Biogeochemical Cycles ◽  
Aerobic Respiration ◽  
Sediment Respiration ◽  
The Earth ◽  
Global Biogeochemical Cycles ◽  
The Impact ◽  
Benthic Animals

While lakes occupy less than 2% of the total surface of the Earth, they play a substantial role in global biogeochemical cycles. For instance, shallow lakes are important sites of carbon metabolism. Aerobic respiration is one of the important drivers of the carbon metabolism in lakes. In this context, bioturbation impacts of benthic animals (biological reworking of sediment matrix and ventilation of the sediment) on sediment aerobic respiration have previously been underestimated. Biological activity is likely to change over the course of a year due to seasonal changes of water temperatures. This study uses microcosm experiments to investigate how the impact of bioturbation (by Diptera, Chironomidae larvae) on lake sediment respiration changes when temperatures increase. While at 5°C, respiration in sediments with and without chironomids did not differ, at 30°C sediment respiration in microcosms with 2000 chironomids per m 2 was 4.9 times higher than in uninhabited sediments. Our results indicate that lake water temperature increases could significantly enhance lake sediment respiration, which allows us to better understand seasonal changes in lake respiration and carbon metabolism as well as the potential impacts of global warming.

scholarly journals Comparative computational modeling of the bat and human immune response to viral infection with the Comparative Biology Immune Agent Based Model

2021 ◽  
Author(s):  
Chase Cockrell ◽  
Gary An
Keyword(s):  
Viral Infection ◽  
Viral Infections ◽  
Comparative Modeling ◽  
Initial Study ◽  
Comparative Biology ◽  
Agent Based Model ◽  
Agent Based ◽  
Human Immune ◽  
The Impact ◽  
Inflammasome Activity

Given the impact of pandemics due to viruses of bat origin there is increasing interest in comparative investigation into the differences between bat and human immune responses. The practice of comparative biology can be enhanced by computational methods used for dynamic knowledge representation to visualize and interrogate the putative differences between the two systems. We present an agent-based model that encompasses and bridges the differences between bat and human responses to viral infection: the Comparative Biology Immune Agent-based Model, or CBIABM. The CBIABM examines differences in innate immune mechanisms between bats and humans, specifically regarding inflammasome activity and Type 1 Interferon dynamics, in terms of tolerance to viral infection. Simulation experiments with the CBIABM demonstrate the efficacy of bat-related features in conferring viral tolerance and also suggest a crucial role for endothelial inflammasome activity as a mechanism for bat systemic viral tolerance and affecting the severity of disease in human viral infections. We hope that this initial study will inspire additional comparative modeling projects to link, compare, and contrast immunological functions shared across different species, and in so doing, provide insight and aid in the preparation for future viral pandemics of zoonotic origin.

scholarly journals Respiratory protease/antiprotease balance determines susceptibility to viral infection and can be modified by nutritional antioxidants

2015 ◽  
Vol 308 (12) ◽  
pp. L1189-L1201 ◽  
Author(s):  
Megan Meyer ◽  
Ilona Jaspers
Keyword(s):  
Viral Infection ◽  
Viral Infections ◽  
Respiratory Epithelium ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Expression Activity ◽  
Respiratory Homeostasis ◽  
The Impact ◽  
Nutritional Antioxidants ◽  
Increased Susceptibility

The respiratory epithelium functions as a central orchestrator to initiate and organize responses to inhaled stimuli. Proteases and antiproteases are secreted from the respiratory epithelium and are involved in respiratory homeostasis. Modifications to the protease/antiprotease balance can lead to the development of lung diseases such as emphysema or chronic obstructive pulmonary disease. Furthermore, altered protease/antiprotease balance, in favor for increased protease activity, is associated with increased susceptibility to respiratory viral infections such as influenza virus. However, nutritional antioxidants induce antiprotease expression/secretion and decrease protease expression/activity, to protect against viral infection. As such, this review will elucidate the impact of this balance in the context of respiratory viral infection and lung disease, to further highlight the role epithelial cell-derived proteases and antiproteases contribute to respiratory immune function. Furthermore, this review will offer the use of nutritional antioxidants as possible therapeutics to boost respiratory mucosal responses and/or protect against infection.

scholarly journals The Impact of Obesity and Lifestyle on the Immune System and Susceptibility to Infections Such as COVID-19

2020 ◽  
Vol 7 ◽  
Author(s):  
Daan L. de Frel ◽  
Douwe E. Atsma ◽  
Hanno Pijl ◽  
Jacob C. Seidell ◽  
Pieter J. M. Leenen ◽  
...  
Keyword(s):  
Immune System ◽  
Chronic Disease ◽  
Viral Infections ◽  
Healthy Lifestyle ◽  
Global Scale ◽  
Lifestyle Factors ◽  
Unhealthy Lifestyle ◽  
Global Challenge ◽  
Literature Searches ◽  
The Impact

Background: COVID-19 is a global challenge to healthcare. Obesity is common in patients with COVID-19 and seems to aggravate disease prognosis. In this review we explore the link between obesity, chronic disease, lifestyle factors and the immune system, and propose societal interventions to enhance global immunity.Search Strategy and Selection Criteria: We performed three literature searches using the keywords (1) coronavirus AND comorbidities, (2) comorbidities AND immune system, and (3) lifestyle factors AND immune system. Results were screened for relevance by the main author and a total of 215 articles were thoroughly analyzed.Results: The relationship between obesity and unfavorable COVID-19 prognosis is discussed in light of the impact of chronic disease and lifestyle on the immune system. Several modifiable lifestyle factors render us susceptible to viral infections. In this context, we make a case for fostering a healthy lifestyle on a global scale.Conclusions: Obesity, additional chronic disease and an unhealthy lifestyle interactively impair immune function and increase the risk of severe infectious disease. In adverse metabolic and endocrine conditions, the immune system is geared toward inflammation. Collective effort is needed to ameliorate modifiable risk factors for obesity and chronic disease on a global scale and increase resistance to viruses like SARS-CoV-2.

scholarly journals A new multi-genomic approach for the study of biogeochemical cycles at global scale: the molecular reconstruction of the sulfur cycle

2017 ◽  
Author(s):  
Valerie De Anda ◽  
Icoquih Zapata-Peñasco ◽  
Bruno Contreras-Moreira ◽  
Augusto Cesar Poot-Hernandez ◽  
Luis E. Eguiarte ◽  
...  
Keyword(s):  
Hydrothermal Vents ◽  
High Throughput Sequencing ◽  
Microbial Mats ◽  
Biogeochemical Cycles ◽  
Global Scale ◽  
Sulfur Cycle ◽  
Novel Approach ◽  
Molecular Machinery ◽  
Genomic Scale ◽  
Global Biogeochemical Cycles

SummaryDespite the great advances in microbial ecology and the explosion of high throughput sequencing, our ability to understand and integrate the global biogeochemical cycles is still limited. Here we propose a novel approach to summarize the complexity of the Sulfur cycle based on the minimum ecosystem concept, the microbial mat model and the relative entropy of protein domains involved in S-metabolism. This methodology produces a single value, called the Sulfur Score (SS), which informs about the specific S-related molecular machinery. After curating an inventory of microorganisms, pathways and genes taking part in this cycle, we benchmark the performance of the SS on a collection of 2,107 non-redundant RefSeq genomes, 900 metagenomes from MG-RAST and 35 metagenomes analyzed for the first time. We find that the SS is able to correctly classify microorganisms known to be involved in the S-cycle, yielding an Area Under the ROC Curve of 0.985. Moreover, when sorting environments the top-scoring metagenomes were hydrothermal vents, microbial mats and deep-sea sediments, among others. This methodology can be generalized to the analysis of other biogeochemical cycles or processes. Provided that an inventory of relevant pathways and microorganisms can be compiled, entropy-based scores could be used to detect environmental patterns and informative samples in multi-genomic scale.

scholarly journals Comparative Computational Modeling of the Bat and Human Immune Response to Viral Infection with the Comparative Biology Immune Agent Based Model

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1620
Author(s):  
Chase Cockrell ◽  
Gary An
Keyword(s):  
Viral Infection ◽  
Viral Infections ◽  
Comparative Modeling ◽  
Initial Study ◽  
Comparative Biology ◽  
Agent Based Model ◽  
Agent Based ◽  
Human Immune ◽  
The Impact ◽  
Inflammasome Activity

Given the impact of pandemics due to viruses of bat origin, there is increasing interest in comparative investigation into the differences between bat and human immune responses. The practice of comparative biology can be enhanced by computational methods used for dynamic knowledge representation to visualize and interrogate the putative differences between the two systems. We present an agent based model that encompasses and bridges differences between bat and human responses to viral infection: the comparative biology immune agent based model, or CBIABM. The CBIABM examines differences in innate immune mechanisms between bats and humans, specifically regarding inflammasome activity and type 1 interferon dynamics, in terms of tolerance to viral infection. Simulation experiments with the CBIABM demonstrate the efficacy of bat-related features in conferring viral tolerance and also suggest a crucial role for endothelial inflammasome activity as a mechanism for bat systemic viral tolerance and affecting the severity of disease in human viral infections. We hope that this initial study will inspire additional comparative modeling projects to link, compare, and contrast immunological functions shared across different species, and in so doing, provide insight and aid in preparation for future viral pandemics of zoonotic origin.

scholarly journals Viral Infection in Renal Transplant Recipients

2012 ◽  
Vol 2012 ◽  
pp. 1-18 ◽  
Author(s):  
Jovana Cukuranovic ◽  
Sladjana Ugrenovic ◽  
Ivan Jovanovic ◽  
Milan Visnjic ◽  
Vladisav Stefanovic
Keyword(s):  
Viral Infection ◽  
Antiviral Therapy ◽  
Viral Infections ◽  
Opportunistic Pathogen ◽  
Renal Transplant Recipients ◽  
Transplant Recipients ◽  
Cellular Effects ◽  
Improved Outcomes ◽  
Prophylactic Antiviral Therapy ◽  
The Impact

Viruses are among the most common causes of opportunistic infection after transplantation. The risk for viral infection is a function of the specific virus encountered, the intensity of immune suppression used to prevent graft rejection, and other host factors governing susceptibility. Although cytomegalovirus is the most common opportunistic pathogen seen in transplant recipients, numerous other viruses have also affected outcomes. In some cases, preventive measures such as pretransplant screening, prophylactic antiviral therapy, or posttransplant viral monitoring may limit the impact of these infections. Recent advances in laboratory monitoring and antiviral therapy have improved outcomes. Studies of viral latency, reactivation, and the cellular effects of viral infection will provide clues for future strategies in prevention and treatment of viral infections. This paper will summarize the major viral infections seen following transplant and discuss strategies for prevention and management of these potential pathogens.

Sign in / Sign up

Export Citation Format

Share Document