Current models predict increases in High Arctic temperatures and precipitation that will have profound impacts on the Arctic hydrological cycle, including enhanced glacial melt and thawing of active layer soils. However, it remains uncertain how these changes will impact the structure of downstream resident freshwater microbial communities and ensuing microbially driven freshwater ecosystem services. Using the Lake Hazen watershed (Nunavut, Canada; 82°N, 71°W) as a sentinel system, we related microbial community composition (16S rRNA gene sequencing) to physicochemical parameters (e.g. dissolved oxygen and nutrients) over an annual hydrological cycle in three freshwater compartments within the watershed: (i) glacial rivers; (ii) active layer thaw-fed streams and waterbodies and (iii) Lake Hazen, into which (i) and (ii) drain. Microbial communities throughout these freshwater compartments were strongly interconnected, hydrologically, and often correlated with the presence of melt-sourced chemicals (e.g. dissolved inorganic carbon) as the melt season progressed. Within Lake Hazen itself, water column microbial communities were generally stable over spring and summer, despite fluctuating lake physicochemistry, indicating that these communities and the potential ecosystem services they provide therein may be resilient to environmental change. This work helps to establish a baseline understanding of how microbial communities and the ecosystem services they provide in Arctic watersheds might respond to future climate change.

• MeSH
• ekosystém MeSH
• jezera mikrobiologie   MeSH
• klimatické změny MeSH
• mikrobiologie vody * MeSH
• mikrobiota * MeSH
• půda MeSH
• půdní mikrobiologie MeSH
• řeky mikrobiologie   MeSH
• RNA ribozomální 16S MeSH
• roční období MeSH
• sladká voda mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Arktida MeSH
• Nunavut MeSH

We studied the differences in a microbial community structure with respect to the water pollution level and seasonal changes. The determination of phylogenetic groups of Bacteria and Archaea was done using fluorescent in situ hybridization (FISH). The total number of microorganisms was determined by direct counting of DAPI (4',6-diamidino-2-phenylindole) stained samples using a fluorescence microscope. Our results showed that the microbial community structure was significantly dependent on the level of water pollution, both in absolute microbial counts and in relative abundance of phylogenetic groups. For surface water with anthropogenic pollution, the microbial community with significant proportion of Betaproteobacteria and Cytophaga-Flavobacterium was characteristic. Gammaproteobacteria were significant in municipal waste water. In microbial communities with low numbers of microorganisms (e.g. non-polluted water and some industrial waste water) represented the significant component groups Alphaproteobacteria and Archaea. The impact of seasonal changes on the microbial distribution was not significant.

• MeSH
• Archaea klasifikace   účinky léků   genetika   MeSH
• Bacteria klasifikace   účinky léků   genetika   MeSH
• hybridizace in situ fluorescenční MeSH
• látky znečišťující vodu toxicita   MeSH
• mikrobiologie vody MeSH
• monitorování životního prostředí MeSH
• roční období MeSH
• znečištění vody škodlivé účinky   analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• Bacteria enzymologie   MeSH
• chitinasy MeSH
• houby MeSH
• půdní mikrobiologie MeSH

• MeSH
• Bacteria izolace a purifikace   MeSH
• lidé MeSH
• orální hygiena MeSH
• sliny mikrobiologie   MeSH
• Check Tag
• lidé MeSH

Peat bog lakes represent important ecosystems in temperate and boreal zones. We investigated the seasonal dynamics of the microbial community in two small peat bog lakes, Kuźnik Olsowy and Kuźnik Bagienny, located in western Poland. Fluorescence in situ hybridization analyses revealed that the bacterial community was dominated by Proteobacteria and Actinobacteria, in addition to a substantial number of archaea. An infrared epifluorescence analysis demonstrated that aerobic anoxygenic phototrophs (AAPs) constituted a significant fraction of bacterial plankton (1-19%). All the bacterial groups exhibited large seasonal changes whose course differed between the studied lakes. While chlorophyll had its maximum during winter or early summer, AAPs peaked in summer, when the growth of this group was stimulated by higher irradiance and elevated water temperatures.

• MeSH
• Archaea klasifikace   genetika   izolace a purifikace   MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   MeSH
• hybridizace in situ fluorescenční MeSH
• jezera mikrobiologie   MeSH
• roční období MeSH
• společenstvo * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Polsko MeSH

Forests are essential biomes for global biogeochemical cycles, and belowground microorganisms have a key role in providing relevant ecosystem services. To predict the effects of environmental changes on these ecosystem services requires a comprehensive understanding of how biotic and abiotic factors drive the composition of microbial communities in soil. However, microorganisms are not homogeneously distributed in complex environments such as soil, with different features affecting microbes at different extent depending on the niche they occupy. Indeed, this spatial heterogeneity hampers the extrapolation of microbial diversity study results from particular habitats to the ecosystem level, even if the resolution of the more recent studies has increased significantly after the standardization of high-throughput sequencing techniques. The present work intends to give a comprehensive view of the knowledge accumulated until date defining the more important drivers determining the structure of forest soil microbial communities from fine to continental scales.

• MeSH
• Bacteria MeSH
• ekosystém * MeSH
• lesy * MeSH
• mikrobiota fyziologie   MeSH
• půda chemie   MeSH
• půdní mikrobiologie * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Mikrobiální flóra trávicího traktu je v poslední době zkoumána ve vztahu k metabolickým onemocněním. Existují vztahy jak k diabetu 1. typu, tak k diabetu 2. typu. Střevní flóra je ovlivňována dietou, fyzickou aktivitou a výrazně se mění po bariatrických chirurgických výkonech. Porod císařským řezem ovlivňuje vývoj střevní flóry a zvyšuje v dalším životě dítěte riziko diabetu 1. typu. Pacientům s obezitou a diabetem 2. typu mohou chybět mikroby protektivní, které v experimentu zlepšují glykoregulaci, nebo naopak přibývat mikroby patogenní, o kterých bylo prokázáno, že mohou dokonce pronikat do abdominální tukové tkáně a podílet se mimo jiné na poruše funkcí jater a systémovém zánětu. Zvažována je i vakcinace proti těmto mikrobům. Pozitivně může mikrobiom ovlivňovat i léčba metforminem. Přenos střevní flóry tzv. transplantací stolice může zlepšovat glykoregulaci. Je pravděpodobné, že ovlivnění střevní flóry se stane novým mechanizmem léčby diabetu.

The microbial flora in the digestive tract has been recently studied in relation to metabolic diseases. There are relations to both type 1 diabetes and type 2 diabetes. The intestinal flora is affected by diet, physical exercise and it significantly changes after bariatric surgeries. Giving birth by caesarean section affects the gut flora development and increases the risk of type 1 diabetes in further life of the child. Obese patients with type 2 diabetes may lack protective microbes which improve glucoregulation in the experiment or on the contrary their patogenous microbes may grow which have been proven to even be able to penetrate into abdominal adipose tissue and play a role, inter alia, in the hepatic impairment and systemic inflammation. Also vaccination against these microbes is under consideration. Microbiome can be also positively affected by metformin treatment. The transfer of intestinal flora by means of fecal transplantation can improve glucoregulation. The influencing of intestinal flora is likely to become a new mechanism of diabetes treatment.

• MeSH
• diabetes mellitus 1. typu * MeSH
• diabetes mellitus 2. typu * MeSH
• lidé MeSH
• metformin terapeutické užití   MeSH
• mikrobiota fyziologie   účinky léků   MeSH
• střeva metabolismus   mikrobiologie   MeSH
• střevní sliznice * metabolismus   mikrobiologie   MeSH
• tuková tkáň MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

The links among the changes in litter chemistry, the activity of extracellular enzymes and the microbial community composition were observed in Quercus petraea litter. Three phases of decomposition could be distinguished. In the early 4-month stage, with high activities of β-glucosidase, β-xylosidase and cellobiohydrolase, 16.4% of litter was decomposed. Hemicelluloses were rapidly removed while cellulose and lignin degradation was slow. In months 4-12, with high endocellulase and endoxylanase activities, decomposition of cellulose prevailed and 31.8% of litter mass was lost. After the third phase of decomposition until month 24 with high activity of ligninolytic enzymes, the litter mass loss reached 67.9%. After 2 years of decay, cellulose decomposition was almost complete and most of the remaining polysaccharides were in the form of hemicelluloses. Fungi largely dominated over bacteria as leaf endophytes and also in the litter immediately before contact with soil, and this fungal dominance lasted until month 4. Bacterial biomass (measured as phospholipid fatty acid content) in litter increased with time but also changed qualitatively, showing an increasing number of Actinobacteria. This paper shows that the dynamics of decomposition of individual litter components changes with time in accordance with the changes in the microbial community composition and its production of extracellular enzymes.

• MeSH
• Actinobacteria enzymologie   metabolismus   MeSH
• Bacteria enzymologie   metabolismus   MeSH
• biodiverzita MeSH
• biomasa MeSH
• dub (rod) MeSH
• glykosidhydrolasy metabolismus   MeSH
• houby enzymologie   MeSH
• polysacharidy metabolismus   MeSH
• půda chemie   MeSH
• půdní mikrobiologie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH

Understanding the ecology of coniferous forests is very important because these environments represent globally largest carbon sinks. Metatranscriptomics, microbial community and enzyme analyses were combined to describe the detailed role of microbial taxa in the functioning of the Picea abies-dominated coniferous forest soil in two contrasting seasons. These seasons were the summer, representing the peak of plant photosynthetic activity, and late winter, after an extended period with no photosynthate input. The results show that microbial communities were characterized by a high activity of fungi especially in litter where their contribution to microbial transcription was over 50%. Differences in abundance between summer and winter were recorded for 26-33% of bacterial genera and < 15% of fungal genera, but the transcript profiles of fungi, archaea and most bacterial phyla were significantly different among seasons. Further, the seasonal differences were larger in soil than in litter. Most importantly, fungal contribution to total microbial transcription in soil decreased from 33% in summer to 16% in winter. In particular, the activity of the abundant ectomycorrhizal fungi was reduced in winter, which indicates that plant photosynthetic production was likely one of the major drivers of changes in the functioning of microbial communities in this coniferous forest.

• MeSH
• Archaea klasifikace   genetika   MeSH
• Bacteria klasifikace   genetika   MeSH
• borovicovité mikrobiologie   MeSH
• ekosystém MeSH
• fotosyntéza MeSH
• genetická transkripce genetika   MeSH
• houby klasifikace   genetika   MeSH
• lesy MeSH
• messenger RNA biosyntéza   genetika   MeSH
• mikrobiota genetika   MeSH
• mykorhiza MeSH
• půda MeSH
• půdní mikrobiologie * MeSH
• roční období MeSH
• stanovení celkové genové exprese MeSH
• stromy mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Soil from Trhové Dušníky (Příbram, Czech Republic) is characterized by its high polymetallic accumulations in Pb-Ag-Zn due to mining and smelting activities. In previous studies performed in our research group, we have evaluated the potential use of amendments that would reduce the mobility and availability of metals such as Hg. We have observed that the application of digestate and fly ash in metal-polluted soil has an impact in immobilizing these metals. However, until now we have lacked information about the effect of these amendments on soil microbial functionality and communities. The multi-contaminated soil was used to grow wheat in a pot experiment to evaluate the impact of digestate and fly ash application in soil microbial communities. Soil samples were collected after 30 and 60 days of treatment. The digestate application improved chemical attributes such as the content in total organic carbon (TOC), water soluble carbon (WSOC), total soluble carbon (C), total soluble nitrogen (N), and inorganic N forms (NO3(-)) as consequence of high content in C and N which is contained in digestate. Likewise, microbial activity was greatly enhanced by digestate application, as was physiological diversity. Bacterial and fungal communities were increased, and the microbial biomass was highly enhanced. These effects were evident after 30 and 60 days of treatment. In contrast, fly ash did not have a remarkable effect when compared to digestate, but soil microbial biomass was positively affected as a consequence of macro- and micro-nutrient sources applied by the addition of fly ash. This study indicates that digestate can be used successfully in the remediation of metal-contaminated soil.

• MeSH
• biomasa MeSH
• dusík analýza   MeSH
• hornictví MeSH
• houby fyziologie   MeSH
• kovy analýza   metabolismus   MeSH
• látky znečišťující půdu analýza   metabolismus   MeSH
• mikrobiální společenstva MeSH
• popel uhelný * MeSH
• pšenice růst a vývoj   MeSH
• půda chemie   MeSH
• půdní mikrobiologie * MeSH
• rtuť analýza   metabolismus   MeSH
• uhlík analýza   chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH