scholarly journals Long-term persistence of crAss-like phage crAss001 is associated with phase variation in Bacteroides intestinalis

BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Andrey N. Shkoporov ◽  
Ekaterina V. Khokhlova ◽  
Niamh Stephens ◽  
Cara Hueston ◽  
Samuel Seymour ◽  
...  
Keyword(s):  
Dynamic Equilibrium ◽  
Phase Variation ◽  
Carrier State ◽  
Complex Environments ◽  
Human Gut ◽  
Rapid Phase ◽  
Host Interaction ◽  
Infected Cells ◽  
Phage Sensitivity

Abstract Background The crAss-like phages are ubiquitous and highly abundant members of the human gut virome that infect commensal bacteria of the order Bacteroidales. Although incapable of lysogeny, these viruses demonstrate long-term persistence in the human gut microbiome, dominating the virome in some individuals. Results Here we show that rapid phase variation of alternate capsular polysaccharides in Bacteroides intestinalis cultures plays an important role in a dynamic equilibrium between phage sensitivity and resistance, allowing phage and bacteria to multiply in parallel. The data also suggests the role of a concomitant phage persistence mechanism associated with delayed lysis of infected cells, similar to carrier state infection. From an ecological and evolutionary standpoint, this type of phage-host interaction is consistent with the Piggyback-the-Winner model, which suggests a preference towards lysogenic or other “benign” forms of phage infection when the host is stably present at high abundance. Conclusion Long-term persistence of bacteriophage and host could result from mutually beneficial mechanisms driving bacterial strain-level diversity and phage survival in complex environments.

scholarly journals Long-term persistence of crAss-like phage crAss001 is associated with phase variation in Bacteroides intestinalis

2020 ◽  
Author(s):  
Andrey N Shkoporov ◽  
Ekaterina V Khokhlova ◽  
Niamh Stephens ◽  
Cara Hueston ◽  
Samuel Seymour ◽  
...  
Keyword(s):  
Dynamic Equilibrium ◽  
Phase Variation ◽  
Carrier State ◽  
Human Gut ◽  
Rapid Phase ◽  
Host Interaction ◽  
Infected Cells ◽  
Phage Sensitivity

The crAss-like phages are ubiquitous and highly abundant members of the human gut virome that infect commensal bacteria of the order Bacteroidales. Although incapable of classical lysogeny, these viruses demonstrate unexplained long-term persistence in the human gut microbiome, dominating the virome in some individuals. Here we demonstrate that rapid phase variation of alternate capsular polysaccharides plays an important role in dynamic equilibrium between phage sensitivity and resistance in B. intestinalis cultures, allowing phage and bacteria to multiply in parallel. The data also suggests the role of concomitant phage persistence mechanisms associated with delayed lysis of infected cells, such as carrier state infection. From an ecological and evolutionary standpoint this type of phage-host interaction is consistent with the Piggyback-the-Winner model, which suggests a preference towards lysogenic or other 'benign' forms of phage infection when the host is stably present at high abundance.

The Effect of Probiotics Supplementation in Maternal-Fetal Care

2020 ◽  
Vol 16 ◽  
Author(s):  
Mahnaz Mardani ◽  
Sadegh Rezapour
Keyword(s):  
Diabetes Mellitus ◽  
Protective Role ◽  
Optimum Dose ◽  
Active Living ◽  
Maternal Weight Gain ◽  
Long Term Effects ◽  
Maternal Weight ◽  
Human Gut ◽  
Obesity And Diabetes

: Pregnancy-related complications can have long-term effects on mother and fetus/child. Microbiome within the human gut is an important factor to maintain optimum health during pregnancy and could possibly reduce the incidence of these complications. Probiotics are active living microorganisms that can provide the host with health benefits such as; immune and hormonal regulatory and metabolic benefits when administered in adequate and optimum dose. Probiotic supplementations also regulate abnormal and unbalanced microflora population that can control the pathogenesis of several diseases like obesity and diabetes. Probiotics also play a protective role in complications like preeclampsia, gestational diabetes mellitus and maternal weight gain and enhance successful outcomes of reproduction. This mini review will thereby summarize the maternal and fetal effects of probiotics during pregnancy.

scholarly journals Taxonomic signatures of cause-specific mortality risk in human gut microbiome

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Aaro Salosensaari ◽  
Ville Laitinen ◽  
Aki S. Havulinna ◽  
Guillaume Meric ◽  
Susan Cheng ◽  
...  
Keyword(s):  
Mortality Risk ◽  
Gut Microbiome ◽  
Human Gut ◽  
Cross Sectional ◽  
Microbiome Composition ◽  
Human Gut Microbiome ◽  
Non Invasive ◽  
Sequencing Technologies

AbstractThe collection of fecal material and developments in sequencing technologies have enabled standardised and non-invasive gut microbiome profiling. Microbiome composition from several large cohorts have been cross-sectionally linked to various lifestyle factors and diseases. In spite of these advances, prospective associations between microbiome composition and health have remained uncharacterised due to the lack of sufficiently large and representative population cohorts with comprehensive follow-up data. Here, we analyse the long-term association between gut microbiome variation and mortality in a well-phenotyped and representative population cohort from Finland (n = 7211). We report robust taxonomic and functional microbiome signatures related to the Enterobacteriaceae family that are associated with mortality risk during a 15-year follow-up. Our results extend previous cross-sectional studies, and help to establish the basis for examining long-term associations between human gut microbiome composition, incident outcomes, and general health status.

scholarly journals Revisiting Ehrlichia ruminantium Replication Cycle Using Proteomics: The Host and the Bacterium Perspectives

2021 ◽  
Vol 9 (6) ◽  
pp. 1144
Author(s):  
Isabel Marcelino ◽  
Philippe Holzmuller ◽  
Ana Coelho ◽  
Gabriel Mazzucchelli ◽  
Bernard Fernandez ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Host Cell ◽  
Cell Metabolism ◽  
Replication Cycle ◽  
Host Cells ◽  
Ehrlichia Ruminantium ◽  
Host Interaction ◽  
Infected Cells ◽  
Related Proteins

The Rickettsiales Ehrlichia ruminantium, the causal agent of the fatal tick-borne disease Heartwater, induces severe damage to the vascular endothelium in ruminants. Nevertheless, E. ruminantium-induced pathobiology remains largely unknown. Our work paves the way for understanding this phenomenon by using quantitative proteomic analyses (2D-DIGE-MS/MS, 1DE-nanoLC-MS/MS and biotin-nanoUPLC-MS/MS) of host bovine aorta endothelial cells (BAE) during the in vitro bacterium intracellular replication cycle. We detect 265 bacterial proteins (including virulence factors), at all time-points of the E. ruminantium replication cycle, highlighting a dynamic bacterium–host interaction. We show that E. ruminantium infection modulates the expression of 433 host proteins: 98 being over-expressed, 161 under-expressed, 140 detected only in infected BAE cells and 34 exclusively detected in non-infected cells. Cystoscape integrated data analysis shows that these proteins lead to major changes in host cell immune responses, host cell metabolism and vesicle trafficking, with a clear involvement of inflammation-related proteins in this process. Our findings led to the first model of E. ruminantium infection in host cells in vitro, and we highlight potential biomarkers of E. ruminantium infection in endothelial cells (such as ROCK1, TMEM16K, Albumin and PTPN1), which may be important to further combat Heartwater, namely by developing non-antibiotic-based strategies.

scholarly journals Latently KSHV-Infected Cells Promote Further Establishment of Latency upon Superinfection with KSHV

2021 ◽  
Vol 22 (21) ◽  
pp. 11994
Author(s):  
Chen Gam ze Letova ◽  
Inna Kalt ◽  
Meir Shamay ◽  
Ronit Sarid
Keyword(s):  
Latent Infection ◽  
Fluorescent Proteins ◽  
Cell Types ◽  
Lytic Cycle ◽  
Viral Reservoir ◽  
Virus Spread ◽  
Viral Genomes ◽  
Latently Infected ◽  
Infected Cells

Kaposi’s sarcoma-associated herpesvirus (KSHV) is a cancer-related virus which engages in two forms of infection: latent and lytic. Latent infection allows the virus to establish long-term persistent infection, whereas the lytic cycle is needed for the maintenance of the viral reservoir and for virus spread. By using recombinant KSHV viruses encoding mNeonGreen and mCherry fluorescent proteins, we show that various cell types that are latently-infected with KSHV can be superinfected, and that the new incoming viruses establish latent infection. Moreover, we show that latency establishment is enhanced in superinfected cells compared to primary infected ones. Further analysis revealed that cells that ectopically express the major latency protein of KSHV, LANA-1, prior to and during infection exhibit enhanced establishment of latency, but not cells expressing LANA-1 fragments. This observation supports the notion that the expression level of LANA-1 following infection determines the efficiency of latency establishment and avoids loss of viral genomes. These findings imply that a host can be infected with more than a single viral genome and that superinfection may support the maintenance of long-term latency.

scholarly journals COVID-19-related anosmia is associated with viral persistence and inflammation in human olfactory epithelium and brain infection in hamsters

2021 ◽  
pp. eabf8396
Author(s):  
Guilherme Dias de Melo ◽  
Françoise Lazarini ◽  
Sylvain Levallois ◽  
Charlotte Hautefort ◽  
Vincent Michel ◽  
...  
Keyword(s):  
Olfactory Epithelium ◽  
Cell Types ◽  
Brain Infection ◽  
Olfactory Neuroepithelium ◽  
Optimal Medical Management ◽  
Infected Cells ◽  
Multiple Cell ◽  
Lung Pathogenesis ◽  
Taste Dysfunction

Whereas recent investigations have revealed viral, inflammatory and vascular factors involved in SARS-CoV-2 lung pathogenesis, the pathophysiology of neurological disorders in COVID-19 remains poorly understood. Olfactory and taste dysfunction are common in COVID-19, especially in mildly symptomatic patients. Here, we conducted a virologic, molecular, and cellular study of the olfactory neuroepithelium of seven patients with COVID-19 presenting with acute loss of smell. We report evidence that the olfactory neuroepithelium may be a major site of SARS-CoV2 infection with multiple cell types, including olfactory sensory neurons, support cells, and immune cells, becoming infected. SARS-CoV-2 replication in the olfactory neuroepithelium was associated with local inflammation. Furthermore, we showed that SARS-CoV-2 induced acute anosmia and ageusia in golden Syrian hamsters, lasting as long as the virus remained in the olfactory epithelium and the olfactory bulb. Finally, olfactory mucosa sampling from patients showing long-term persistence of COVID-19-associated anosmia revealed the presence of virus transcripts and of SARS-CoV-2-infected cells, together with protracted inflammation. SARS-CoV-2 persistence and associated inflammation in the olfactory neuroepithelium may account for prolonged or relapsing symptoms of COVID-19, such as loss of smell, which should be considered for optimal medical management of this disease.

scholarly journals Dragonfly Inspired Smart Soft Robot

2020 ◽  
Author(s):  
Vardhman Kumar ◽  
Ung Hyun Ko ◽  
Yilong Zhou ◽  
Jiaul Hoque ◽  
Gaurav Arya ◽  
...  
Keyword(s):  
Environmental Remediation ◽  
Stimuli Responsive ◽  
Complex Environments ◽  
Soft Robots ◽  
Responsive Materials ◽  
Environmental Perturbations ◽  
Integration Strategies ◽  
Soft Actuators ◽  
Harsh Conditions

Recent advancements in soft robotics have led to the development of compliant robots that can exhibit complex motions driven by living cells(1, 2), chemical reactions(3), or electronics(4). Further innovations are however needed to create the next generation of soft robots that can carry out advanced functions beyond locomotion. Here we describe DraBot—a dragonfly-inspired, entirely soft, multifunctional robot that combines long-term locomotion over water surface with sensing, responding, and adaptation capabilities. By integrating soft actuators, stimuli-responsive materials, and microarchitectural features, we created a circuitry of pneumatic and microfluidic logic that enabled the robot to undergo user- and environment-controlled (pH) locomotion, including navigating hazardous (acidic) conditions. DraBot was also engineered to sense additional environmental perturbations (temperature) and detect and clean up chemicals (oil). The design, fabrication, and integration strategies demonstrated here pave a way for developing futuristic soft robots that can acclimatize and adapt to harsh conditions while carrying out complex tasks such as exploration, environmental remediation, and health care in complex environments.

scholarly journals Integration of Indonesian Coffee Markets with World Coffee Markets

2021 ◽  
Vol 2 (1) ◽  
pp. 33
Author(s):  
Haposan Orlando Napitupulu ◽  
Ana Arifatus Sa'diyah ◽  
Farah Mutiara
Keyword(s):  
Time Series Data ◽  
Dynamic Equilibrium ◽  
Secondary Data ◽  
Series Data ◽  
Short Term ◽  
Robusta Coffee ◽  
Long Run ◽  
Relationship Of ◽  
Coffee Markets

This study aims to analyze the integration of the Arabica and Robusta coffee markets in Indonesia with world coffee prices. The study uses secondary data in the form of annual time series data during the period 1985 - 2015. The study uses the VECM analysis method. This method explains the relationship of long-term dynamic equilibrium and short-term equilibrium in a system of equations. The analysis shows that Indonesian and world Arabica coffee is not integrated in the long term or the short term. In Robusta coffee VECM estimation analysis shows that there is a significant value at the 10% level in a long-term relationship with a value of 0.08579, which means that there is a short-term relationship between world Robusta coffee prices and domestic Robusta coffee prices in the previous year, but no relationship in the long run.

scholarly journals Transketolase is involved in the control of Sigma B during chronic infection by Staphylococcus aureus

2019 ◽  
Author(s):  
Xin Tan ◽  
Elodie Ramond ◽  
Anne Jamet ◽  
Baptiste Decaux-Tramoni ◽  
Marion Dupuis ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Wild Type Strain ◽  
Pentose Phosphate ◽  
Chronic Infections ◽  
Master Regulators ◽  
Sigma B ◽  
Viable Bacteria ◽  
Infected Cells ◽  
Slow Growing

AbstractStaphylococcus aureus is a leading cause of both acute and chronic infections in humans. Its ability to persist within host cells is thought to play an important role in chronicity and treatment failures. The importance of the pentose phosphate pathway (PPP) during S. aureus chronic infection is currently largely unexplored. Here, we focused on one key PPP enzyme, transketolase. We showed that inactivation of the unique gene encoding transketolase activity in S. aureus USA300 (Δtkt) led to an impaired growth in broth. Using time-lapse video imaging, we correlated this phenotype with a defect in early intracellular proliferation compared to wild-type strain. As determined by metabolomic analysis, tkt inactivation also had an important impact on S. aureus metabolism. We then monitored long-term intracellular persistence over 10 days by counting of viable bacteria. Unexpectedly for such a slow-growing strain, the Δtkt mutant was almost completely eliminated by endothelial cells after ten days, as opposed to a prototypical slow-growing ΔhemDBL mutant for which we recovered 1,000 fold more viable bacteria. We found that in infected cells, the transcriptional activity of the two master regulators Sigma B and RpiRc was drastically reduced in the Δtkt mutant compared to wild-type strain. Concomitantly, RNAIII transcription was strongly increased. This transcriptional profile is likely to explain the inability of this slow-growing mutant to sustain long-term intracellular survival, suggesting that TKT -or a functional PPP-is required for intracellular bacteria to enable a transcriptional program geared towards persistence.ImportanceStaphylococcus aureus is a leading cause of severe bacterial infections. This bacterium is readily internalized by non-professional phagocytes and infected cells have been proposed to play an important role in chronic infections and treatment failures.Here, we show the importance of the unique transketolase TKT of S. aureus USA300 in bacterial adaptation during chronic intracellular infection. We show that TKT is mandatory for the metabolomic homeostasis of S. aureus during intracellular persistence. This work unravels the critical role of TKT in the transcriptional regulation of the master regulators Sigma B, RpiRc and RNAIII linking the pentose phosphate pathway to the control of chronic S. aureus infections.

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