The common grape (Vitis vinifera L.) has been cultivated for thousands of years. Nowadays, it is cultivated using a variety of tillage practices that affect the structure of the soil microbial communities and thus the health of the vine.
View Article and Find Full Text PDFEarth harbors unique environments where only microorganisms adapted to extreme conditions, known as extremophiles, can survive. This study focused on a high-altitude meltwater pond, located in the Puna de Atacama, Dry Andes. The extremophilic bacteria of this habitat must adapt to a range of extremities, including cold and dry climate, high UV radiation, high daily temperature fluctuations, low-nutrient availability, and negative water balance.
View Article and Find Full Text PDFThe taxonomic and metabolic diversity of prokaryotes and their adaptability to extreme environmental parameters have allowed extremophiles to find their optimal living conditions under extreme conditions for one or more environmental parameters. Natural habitats abundant in extremophilic microorganisms are relatively rare in Hungary. Nevertheless, alkaliphiles and halophiles can flourish in shallow alkaline lakes (soda pans) and saline (solonetz) soils, where extreme weather conditions favor the development of unique bacterial communities.
View Article and Find Full Text PDFSoil salinity and sodicity is a worldwide problem that affects the composition and activity of bacterial communities and results from elevated salt and sodium contents. Depending on the degree of environmental pressure and the combined effect of other factors, haloalkalitolerant and haloalkaliphilic bacterial communities will be selected. These bacteria play a potential role in the maintenance and restoration of salt-affected soils; however, until recently, only a limited number of studies have simultaneously studied the bacterial diversity and activity of saline-sodic soils.
View Article and Find Full Text PDFExtensive research has provided a wealth of data on prokaryotes in caves and their role in biogeochemical cycles. Ice caves in carbonate rocks, however, remain enigmatic environments with limited knowledge of their microbial taxonomic composition. In this study, bacterial and archaeal communities of the Obstans Ice Cave (Carnic Alps, Southern Austria) were analyzed by next-generation amplicon sequencing and by cultivation of bacterial strains at 10 °C and studying their metabolism.
View Article and Find Full Text PDFThe physical and chemical characteristics of the bedrock, along with the geological and hydrological conditions of karst caves may influence the taxonomic and functional diversity of prokaryotes. Most studies so far have focused on microbial communities of caves including only a few samples and have ignored the chemical heterogeneity of different habitat types such as sampling sites, dripping water, carbonate precipitates, cave walls, cave sediment and surface soils connected to the caves. The aim of the present study was to compare the morphology, the composition and physiology of the microbiota in caves with similar environmental parameters (temperature, host rock, elemental and mineral composition of speleothems) but located in different epigenic karst systems.
View Article and Find Full Text PDFIn freshwaters, microbial communities are of outstanding importance both from ecological and public health perspectives, however, they are threatened by the impact of global warming. To reveal how different prokaryotic communities in a large temperate river respond to environment conditions related to climate change, the present study provides the first detailed insight into the composition and spatial and year-round temporal variations of planktonic and epilithic prokaryotic community. Microbial diversity was studied using high-throughput next generation amplicon sequencing.
View Article and Find Full Text PDFIn this study, we examined the effect of salinity and alkalinity on the metabolic potential and taxonomic composition of microbiota inhabiting the sodic soils in different plant communities. The soil samples were collected in the Pannonian steppe (Hungary, Central Europe) under extreme dry and wet weather conditions. The metabolic profiles of microorganisms were analyzed using the MicroResp method, the bacterial diversity was assessed by cultivation and next-generation amplicon sequencing based on the 16S rRNA gene.
View Article and Find Full Text PDFAttachment of microorganisms to natural or artificial surfaces and the development of biofilms are complex processes which can be influenced by several factors. Nevertheless, our knowledge on biofilm formation in karstic environment is quite incomplete. The present study aimed to examine biofilm development for a year under controlled conditions in quasi-stagnant water of a hydrothermal spring cave located in the Buda Thermal Karst System (Hungary).
View Article and Find Full Text PDFSoils play an important role in the ecosystem of karstic landscapes both as a buffer zone and as a source of acidity to belowground water. Although the microbiota of karstic soils is known to have a great effect on karstification processes, the activity and composition of these communities are largely unknown. This study gives a comparative analysis of soil microbial profiles from different parts of a doline located at Aggtelek, Hungary.
View Article and Find Full Text PDFMicrobial ecology of permafrost, due to its ecological and astrobiological importance, has been in the focus of studies in past decades. Although permafrost is an ancient and stable environment, it is also subjected to current climate changes. Permafrost degradation often results in generation of thaw ponds, a phenomenon not only reported mainly from polar regions but also present in high-altitude permafrost environments.
View Article and Find Full Text PDFPeriglacial and volcanic environments are considered terrestrial analogs of Mars with regard to astrobiological characteristics due to their specific set of extreme features. Ojos del Salado, the highest volcano on Earth (6893 m a.s.
View Article and Find Full Text PDFAmorphous calcium carbonate (ACC) is a precursor of crystalline calcium carbonates that plays a key role in biomineralization and polymorph evolution. Here, we show that several bacterial strains isolated from a Hungarian cave produce ACC and their extracellular polymeric substance (EPS) shields ACC from crystallization. The findings demonstrate that bacteria-produced ACC forms in water-rich environment at room temperature and is stable for at least half year, which is in contrast to laboratory-produced ACC that needs to be stored in a desiccator and kept below 10 °C for avoiding crystallization.
View Article and Find Full Text PDFKynurenic acid (KYNA) is one of the most significant metabolite of the kynurenine pathway both in terms of functional and potential therapeutic value. It is an N-methyl-D-aspartate (NMDA) receptor antagonist, but it can also activate the G-protein coupled receptor 35 (GPR35), which shares several structural and functional properties with cannabinoid receptors. Previously our group demonstrated that systemic chronic KYNA treatment altered opioid receptor G-protein activity.
View Article and Find Full Text PDFMost cyanobacterial organisms included in the genus can produce a wide repertoire of secondary metabolites. In the mid-2010s, summer cyanobacterial blooms of sp. occurred regularly in Lake Balaton.
View Article and Find Full Text PDFIn April 2014, dual bloom of green algae and purple bacteria occurred in a shallow, alkaline soda pan (Kiskunság National Park, Hungary). The water was only 5 cm deep, in which an upper green layer was clearly separated from a near-sediment purple one. Based on microscopy and DNA-based identification, the upper was inhabited by a dense population of the planktonic green alga, Oocystis submarina Lagerheim, while the deeper layer was formed by purple, bacteriochlorophyll-containing bacteria, predominated by Thiorhodospira and Rhodobaca.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
June 2019
A Gram-stain-negative, aerobic, non-motile and coccus-shaped bacterium, designated strain FeSDHB5-19, was isolated from a biofilm sample collected from a radioactive thermal spring (Budapest, Hungary), after exposure to 5 kGy gamma radiation. A polyphasic approach was used to study the taxonomic properties of strain FeSDHB5-19, which had highest 16S rRNA gene sequence similarity to Deinococcus antarcticus G3-6-20 (96.5 %).
View Article and Find Full Text PDFThe thermal waters of Gellért Hill discharge area of the Buda Thermal Karst System (Hungary) are characterized by high (up to 1000 Bq/L) Rn-activity due to the radium-accumulating biogeochemical layers. Samples were taken from these ferruginous and calcareous layers developed on spring cave walls and water surface. Accumulation of potentially toxic metals (e.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
March 2019
Two alkaliphilic and moderately halophilic bacterial strains B16-10 and Z23-18 characterized by optimal growth at pH 9.0-10.0 and 5 % (w/v) NaCl, were isolated from the rhizosphere soil of the bayonet grass (Bolboschoenus maritimus) in the Kiskunság National Park, Hungary.
View Article and Find Full Text PDFThe spatial response of epiphytic diatom communities to environmental stress was studied in a moderately saline wetland area located in the plain of Danube-Tisza Interfluve, Hungary. The area is characterised by World War II bomb crater ponds and can be regarded as an excellent ecological model system where the dispersion of species is slightly limited by distance. To study the effect of environmental variables on the communities, canonical correspondence analysis was applied.
View Article and Find Full Text PDFThe Buda Thermal Karst System (BTKS) is an extensive active hypogenic cave system located beneath the residential area of the Hungarian capital. At the river Danube, several thermal springs discharge forming spring caves. To reveal and compare the morphological structure and prokaryotic diversity of reddish-brown biofilms developed on the carbonate rock surfaces of the springs, scanning electron microscopy (SEM), and molecular cloning were applied.
View Article and Find Full Text PDFNumerous studies demonstrate the significant role of central β-endorphin and its receptor, the μ-opioid receptor (MOR), in sodium intake regulation. The present study aimed to investigate the possible relationship between chronic high-NaCl intake and brain endogenous MOR functioning. We examined whether short-term (4 days) obligatory salt intake (2% NaCl solution) in rats induces changes in MOR mRNA expression, G-protein activity and MOR binding capacity in brain regions involved in salt intake regulation.
View Article and Find Full Text PDFActa Microbiol Immunol Hung
December 2018
Karst areas have great environmental importance as sources of subsurface water and often maintain very sensitive ecosystems. In recent years, increasing number of microbiological studies focused on the bacterial communities of karst soils. In this study, diversity examinations on two distinct Hungarian karst areas, Aggtelek and Tapolca, were performed using parallel cultivation and molecular cloning methods.
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