Impact of Saharan dust on particulate matter characteristics in an urban and a natural locality in Central Europe.

In late March to early April 2024, an unusually high amount of sand dust was wind-blown to Europe from the Sahara Desert. Most of mainland Europe was affected by these sand dust particles. As a result, Central Europe experienced an exceptionally high increase in air pollution.

MoaB2, a newly identified transcription factor, binds to σ in .

In mycobacteria, σ is the primary sigma factor. This essential protein binds to RNA polymerase (RNAP) and mediates transcription initiation of housekeeping genes. Our knowledge about this factor in mycobacteria is limited.

Toxic metals in cyanobacterial mat of Big Lachman Lake, James Ross Island, Antarctica.

The northern part of James Ross Island is the largest deglaciated area in the Antarctic Peninsula region with a unique ecosystem created during the Late Glacial. This research aims to evaluate the degree of contamination of the locality with toxic metals (As, Hg, Cd, and Pb) through bioindicators in the aquatic environment-colonies of cyanobacteria and algae. For this purpose, bottom lake sediments of Big Lachman Lake were studied for contents of Fe, As, Hg, Cd, Pb, Cr, Co, Ni, Cu, and Zn, as well as samples of cyanobacterial mat, in which Fe, As, Hg, Cd, and Pb were determined.

An extensive individual particle analysis of solid airborne particles collected in a moderately urbanized area.

Detailed individual particle characterization of PM, in terms of particle size, morphology, and elemental composition, was done using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy. The samples were collected in four localities in the Czech Republic (Central Europe), three of which are medium-sized cities, and one is a natural locality in the mountains. More than 1600 particles obtained from each locality were evaluated.

Thainema gen. nov. (Leptolyngbyaceae, Synechococcales): A new genus of simple trichal cyanobacteria isolated from a solar saltern environment in Thailand.

Simple trichal types constitute a group of cyanobacteria with an abundance of novel, often cryptic taxa. Here, we investigated material collected from wet surface-soil in a saline environment in Petchaburi Province, central Thailand. A morphological comparison of the isolated strain with similar known species, as well as its phylogenetic and species delimitation analyses based on the combined datasets of other related organisms, especially simple trichal cyanobacteria, revealed that the material of this study represented an independent taxon.

Tenebriella gen. nov. - The dark twin of Oscillatoria.

Oscillatoria has long been known to be polyphyletic. After recent resequencing of the reference strain for this genus, many Oscillatoria-like groups phylogenetically distant from the type species O. princeps remained unresolved.

Determination of cadmium in lichens by solid sampling graphite furnace atomic absorption spectrometry (SS-GF-AAS).

The determination of trace metal contents directly from a solid sample is a trend in modern atomic spectrometry. The aim of this study was to develop an analytical method for the routine determination of Cd in lichens using solid sampling graphite furnace atomic absorption spectrometry (SS-GF-AAS). For the determination of Cd, the temperature program of the graphite furnace was optimized using a mixed matrix modifier (Pd + Mg (NO) + Triton X-100).

Characterization of novel lectins from Burkholderia pseudomallei and Chromobacterium violaceum with seven-bladed β-propeller fold.

Burkholderia pseudomallei and Chromobacterium violaceum are bacteria of tropical and subtropical soil and water that occasionally cause fatal infections in humans and animals. Microbial lectins mediate the adhesion of organisms to host cells, which is the first phase in the development of infection. Here we report the discovery of two novel lectins from the above-mentioned bacteria - BP39L and CV39L.

Synthesis of β-d-galactopyranoside-Presenting Glycoclusters, Investigation of Their Interactions with Lectin A (PA-IL) and Evaluation of Their Anti-Adhesion Potential.

is an opportunistic human pathogen associated with cystic fibrosis. This bacterium produces, among other virulence factors, a soluble d-galactose-specific lectin PA-IL (LecA). PA-IL plays an important role in the adhesion to the host cells and is also cytotoxic.

Simultaneous determination of cadmium and iron in different kinds of cereal flakes using high-resolution continuum source atomic absorption spectrometry.

A method for simultaneous determination of cadmium and iron in cereal flakes using high-resolution continuum source graphite furnace atomic absorption spectrometry is presented. Sample digest is introduced into the graphite furnace together with Pd/Mg(NO) modifier. The primary absorption line of cadmium and adjacent secondary line of iron are used for the determination.

Correction to: Model of Mercury Flux Associated with Volcanic Activity.

The original version of this article contained a mistake in Fig. 2. The country names have been missed in the figure legend along with the X-axis.

Selecting appropriate variables for detecting grassland to cropland changes using high resolution satellite data.

Grassland is one of the most represented, while at the same time, ecologically endangered, land cover categories in the European Union. In view of the global climate change, detecting its change is growing in importance from both an environmental and a socio-economic point of view. A well-recognised tool for Land Use and Land Cover (LULC) Change Detection (CD), including grassland changes, is Remote Sensing (RS).

Model of Mercury Flux Associated with Volcanic Activity.

Volcanic activity is one of the primary sources of mercury in the earth's ecosystem. In this work, volcanic rocks from four geotectonically distinct localities (the Czech Republic - intraplate, rift-related alkaline basaltic rocks; Iceland - hotspot/rift-related tholeiitic basaltic rocks; Japan - island arc calc-alkaline andesites; and Alaska - continental arc calc-alkaline dacites) were studied. Ultra-trace Hg contents in all samples ranged from 0.

Structure and properties of AB21, a novel Agaricus bisporus protein with structural relation to bacterial pore-forming toxins.

We report the characterization of the dimeric protein AB21 from Agaricus bisporus, one of the most commonly and widely consumed mushrooms in the world. The protein shares no significant sequence similarity with any protein of known function, and it is the first characterized member of its protein family. The coding sequence of the ab21 gene was determined and the protein was expressed in E.

The contents and distributions of cadmium, mercury, and lead in Usnea antarctica lichens from Solorina Valley, James Ross Island (Antarctica).

Lichens are efficient and cost-effective biomonitors of the environment. Their geographic distribution together with their slow growth rate enable investigation of the deposition patterns of various elements and substances. In this research, levels of cadmium, lead, and mercury in Usnea antarctica lichens in the area of James Ross Island, Antarctica, were investigated.

Mercury species in formerly contaminated soils and released soil gases.

Total mercury (T-Hg), elemental mercury (Hg), methylmercury (MeHg), phenylmercury (PhHg), and gaseous elemental mercury (GEM) species were determined in soils formerly contaminated by different processes from two sites in the Czech Republic. Analytical methods involved atomic absorption spectrometry (AAS) using a single-purpose Advanced Mercury Analyser AMA-254 and radiochemical neutron activation analysis (RNAA) for T-Hg determination, a thermal desorption method was used for Hg determination, gas chromatography coupled with atomic fluorescence spectrometry (GC-AFS) was employed for assay of MeHg and PhHg, while GEM measurement was carried out using a portable Zeeman-AAS device Lumex RA-915. The first sampling site was in the surroundings of a former PhHgCl-based fungicide processing plant next to Příbram (central Bohemia).

Leaching of mercury from seal carcasses into Antarctic soils.

More than 400 seal mummies and skeletons are now mapped in the northern part of James Ross Island, Antarctica. Decomposing carcasses represent a rare source of both organic matter and associated elements for the soil. Owing to their high trophic position, seals are known to carry a significant mercury body burden.

Effects of the soil microbial community on mobile proportions and speciation of mercury (Hg) in contaminated soil.

The precise characterization of the behavior of individual microorganisms in the presence of increased mercury contents in soil is necessary for better elucidation of the fate of mercury in the soil environment. In our investigation, resistant bacterial strains isolated from two mercury contaminated soils, represented by Paenibacillus alginolyticus, Burkholderia glathei, Burkholderia sp., and Pseudomonas sp.

Structural insights into Aspergillus fumigatus lectin specificity: AFL binding sites are functionally non-equivalent.

The Aspergillus fumigatus lectin AFL was recently described as a new member of the AAL lectin family. As a lectin from an opportunistic pathogen, it might play an important role in the interaction of the pathogen with the human host. A detailed study of structures of AFL complexed with several monosaccharides and oligosaccharides, including blood-group epitopes, was combined with affinity data from SPR and discussed in the context of previous findings.

Analysis of mercury and other heavy metals accumulated in lichen Usnea antarctica from James Ross Island, Antarctica.

The study was designed to investigate the content and distribution of selected heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Fe, Pb and Zn) in samples of fruticose macrolichen Usnea antarctica from James Ross Island. A special emphasis was devoted to mercury and its species (elemental mercury and methylmercury). It was found that mercury contents were relatively high (up to 2.

X-ray vs. NMR structure of N-terminal domain of δ-subunit of RNA polymerase.

The crystal structure of the N-terminal domain of the RNA polymerase δ subunit (Nδ) from Bacillus subtilis solved at a resolution of 2.0Å is compared with the NMR structure determined previously. The molecule crystallizes in the space group C222(1) with a dimer in the asymmetric unit.

Seasonal variability of mercury contents in street dust in Brno, Czech Republic.

Environmental contamination by mercury carries serious risks to the biosphere. Urban agglomerations burdened with traffic are characterized by substantial dust levels, including high concentrations of pollutants bound to particulate matter. In this research, the content of particulate mercury in street dust was investigated in relation to the season and traffic intensity.

A soluble fucose-specific lectin from Aspergillus fumigatus conidia--structure, specificity and possible role in fungal pathogenicity.

Aspergillus fumigatus is an important allergen and opportunistic pathogen. Similarly to many other pathogens, it is able to produce lectins that may be involved in the host-pathogen interaction. We focused on the lectin AFL, which was prepared in recombinant form and characterized.