Search results for "mikrobisto"
showing 10 items of 74 documents
Prokaryotic assemblages within permafrost active layer at Edmonson Point (Northern Victoria Land, Antarctica)
2018
This study was aimed at gaining insights on the prokaryotic community (in terms of both taxonomic composition and activities) inhabiting the active layer at Edmonson Point, an ice-free area on the eastern slope at the foot of Mount Melbourne (Northern Victoria Land, Antarctica). Samples were collected during the thawing period, when microbial physiological activities are restored to utilize previously frozen organic substrates. Despite the very small cell sizes (600 daltons) substrates, as indicated also by the obtained rates of enzymatic hydrolytic activities over proteolytic, glycolitic and phosphoric compounds. Taxonomical composition showed that Proteobacteria, Actinobacteria and Firmic…
Identification of Gut Microbial Lysine and Histidine Degradation and CYP-Dependent Metabolites as Biomarkers of Fatty Liver Disease
2023
Numerous studies have described specific metabolites as biomarkers ofsevere liver diseases, but very few have measured gut microbiota (GM)-produced metab-olites in fatty liver disease. We aimed atfinding GM signatures and metabolite markersin plasma and feces related to high liver fat content. Based on imaging, we dividedstudy participants into low (,5%, LF,n= 25) and high (.5%, HF,n= 39) liver fatgroups. Fecal (LFn= 14, HFn= 25) and plasma (LFn= 11, HFn= 7) metabolomes ofsubsets of participants were studied using liquid chromatography/high resolution massspectrometry. The GM were analyzed using 16S rRNA gene sequencing. Additionally,blood clinical variables and diet were studied. Dyslipide…
Tracing the fate of microplastic carbon in the aquatic food web by compound-specific isotope analysis
2019
Increasing abundance of microplastics (MP) in marine and freshwaters is currently one of the greatest environmental concerns. Since plastics are fairly resistant to chemical decomposition, breakdown and reutilization of MP carbon complexes requires microbial activity. Currently, only a few microbial isolates have been shown to degrade MPs, and direct measurements of the fate of the MP carbon are still lacking. We used compound-specific isotope analysis to track the fate of fully labelled 13C-polyethylene (PE) MP carbon across the aquatic microbial-animal interface. Isotopic values of respired CO2 and membrane lipids showed that MP carbon was partly mineralized and partly used for cell growt…
Out of sight : Profiling soil characteristics, nutrients and bacterial communities affected by organic amendments down to one meter in a long-term ma…
2019
Common soil characteristics, nutrients and microbial activity at deeper soil depths are topics seldom covered in agricultural studies. Biogeochemical cycles in deep soils are not yet fully understood. This study investigates the effect of different mineral and organic fertilisation on soil organic matter dynamics, nutrients and bacterial community composition in the first meter of the soil profiles in the long-term maize cropping system experiment Tetto Frati, near the Po River in northern Italy. The following treatments have been applied since 1992: 1) crop residue removal (CRR), 2) crop residue incorporation (CRI), 3) crop residue removal with bovine slurry fertilisation (SLU), 4) crop re…
Integrating Decomposers, Methane-Cycling Microbes and Ecosystem Carbon Fluxes Along a Peatland Successional Gradient in a Land Uplift Region
2021
AbstractPeatlands are carbon dioxide (CO2) sinks that, in parallel, release methane (CH4). The peatland carbon (C) balance depends on the interplay of decomposer and CH4-cycling microbes, vegetation, and environmental conditions. These interactions are susceptible to the changes that occur along a successional gradient from vascular plant-dominated systems to Sphagnum moss-dominated systems. Changes similar to this succession are predicted to occur from climate change. Here, we investigated how microbial and plant communities are interlinked with each other and with ecosystem C cycling along a successional gradient on a boreal land uplift coast. The gradient ranged from shoreline to meadows…
Gut Microbiota, Microbial Metabolites and Human Physical Performance
2021
Trillions of microbes inhabiting the gut modulate the metabolism of the host. Cross-sectional studies have reported associations between physical performance and the gut microbiota (GM). Physical activity seems to increase GM diversity and the abundance of certain health-beneficial microbes. We reviewed the evidence from longitudinal studies on the connection between physically active lifestyle or long-term exercise interventions and the GM. We made literature searches using databases of Web of Science and PubMed Medline to collect human studies showing or not the associations between the GM and exercise. Many controversies exist in the studies. However, the longitudinal studies show that f…
Wastewater constituents impact biofilm microbial community in receiving streams
2022
Microbial life in natural biofilms is dominated by prokaryotes and microscopic eukaryotes living in dense association. In stream ecosystems, microbial biofilms influence primary production, elemental cycles, food web interactions as well as water quality. Understanding how biofilm communities respond to anthropogenic impacts, such as wastewater treatment plant (WWTP) effluent, is important given the key role of biofilms in stream ecosystem function. Here, we implemented 16S and 18S rRNA gene sequencing of stream biofilms upstream (US) and downstream (DS) of WWTP effluents in four Swiss streams to test how bacterial and eukaryotic communities respond to wastewater constituents. Stream biofil…
Vertical stratification of bacteria and archaea in sediments of a small boreal humic lake
2019
ABSTRACT Although sediments of small boreal humic lakes are important carbon stores and greenhouse gas sources, the composition and structuring mechanisms of their microbial communities have remained understudied. We analyzed the vertical profiles of microbial biomass indicators (PLFAs, DNA and RNA) and the bacterial and archaeal community composition (sequencing of 16S rRNA gene amplicons and qPCR of mcrA) in sediment cores collected from a typical small boreal lake. While microbial biomass decreased with sediment depth, viable microbes (RNA and PLFA) were present all through the profiles. The vertical stratification patterns of the bacterial and archaeal communities resembled those in mar…
Blocking Activin Receptor Ligands Is Not Sufficient to Rescue Cancer-Associated Gut Microbiota—A Role for Gut Microbial Flagellin in Colorectal Cance…
2019
Colorectal cancer (CRC) and cachexia are associated with the gut microbiota and microbial surface molecules. We characterized the CRC-associated microbiota and investigated whether cachexia affects the microbiota composition. Further, we examined the possible relationship between the microbial surface molecule flagellin and CRC. CRC cells (C26) were inoculated into mice. Activin receptor (ACVR) ligands were blocked, either before tumor formation or before and after, to increase muscle mass and prevent muscle loss. The effects of flagellin on C26-cells were studied in vitro. The occurrence of similar phenomena were studied in murine and human tumors. Cancer modulated the gut microbiota witho…
The Association between Cardiorespiratory Fitness and Gut Microbiota Composition in Premenopausal Women
2017
Abstract The aim of this study was to investigate the association between cardiorespiratory fitness and gut microbiota composition in premenopausal women. The participants consisted of 71 premenopausal Finnish women (aged 19–49 years). Gut microbiota were analyzed using flow cytometry, 16S rRNA gene hybridization and DNA-staining. Maximum oxygen uptake (VO₂ₘₐₓ) was assessed by respiratory gas analyzer and body composition by Bioimpdance. We found that participants with low VO₂ₘₐₓ had lower Bacteroides, but higher Eubacterium rectale-Clostridium coccoides than the high VO₂ₘₐₓ group (p < 0.05 for all). VO₂ₘₐₓ was inversely associated with EreC (r = −0.309, p = 0.01) but not with other bact…