Winter diet analysis in Rhinolophus euryale (Chiroptera)

We investigated the winter food of Mediterranean horseshoe bats (Rhinolophus euryale) in four winter cave roosts in southern Slovakia and northern Hungary and investigated the relationship between food and ambient temperature. The bats were active during the whole winter period and they produced excrement throughout the entire hibernation period, even when outside temperatures dropped below zero. The guano was in two forms, containing (1) prey items and (2) non-prey items. The identifiable items belonged to lepidopteran species, but only one was identified, on the basis of the genital fragments, the moth Colotois pennaria, which was the main prey species in autumn and early winter. Our results shed light on the extraordinarily high level of activity in this bat species during winter hibernation, which in temperate regions is a strategy that enables bats to survive when prey is reduced or absent. In R. euryale, the torpor in the course of hibernation is not continuous and our results help to explain how energy losses caused by bat movements are covered.     

Changes of lipid domains in Bacillus subtilis cells with disrupted cell wall peptidoglycan

The cell wall is responsible for cell integrity and the maintenance of cell shape in bacteria. The Gram-positive bacterial cell wall consists of a thick peptidoglycan layer located on the outside of the cytoplasmic membrane. Bacterial cell membranes, like eukaryotic cell membranes, are known to contain domains of specific lipid and protein composition. Recently, using the membrane-binding fluorescent dye FM4-64, helix-like lipid structures extending along the long axis of the cell and consisting of negatively charged phospholipids were detected in the rod-shaped bacterium Bacillus subtilis. It was also shown that the cardiolipin-specific dye, nonyl acridine orange (NAO), is preferentially distributed at the cell poles and in the septal regions in both Escherichia coli and B. subtilis. These results suggest that phosphatidylglycerol is the principal component of the observed spiral domains in B. subtilis. Here, using the fluorescent dyes FM4-64 and NAO, we examined whether these lipid domains are linked to the presence of cell wall peptidoglycan. We show that in protoplasted cells, devoid of the peptidoglycan layer, helix-like lipid structures are not preserved. Specific lipid domains are also missing in cells depleted of MurG, an enzyme involved in peptidoglycan synthesis, indicating a link between lipid domain formation and peptidoglycan synthesis.     

A novel,combined approach to assessing species delimitation and biogeography within the well-known desmid species <Emphasis Type="Italic">Micrasterias fimbriata</Emphasis> and <Emphasis Type="Italic">M. rotata</Emphasis> (Desmidiales,Steptophyta)

Morphological species of freshwater microalgae often have broad geographic distribution. However, traditional species concepts have been challenged by the results of molecular phylogenetic analyses that mostly indicate higher diversity than was previously recognized by purely morphological approaches. A degree of phenotypic differentiation or different geographic distribution of species defined by molecular data remains largely unknown. In this study, we analyzed a pair of well-known and widely distributed desmid species (Micrasterias fimbriata and M. rotata) and tested for their phylogenetic and morphological homogeneity as well as their geographic distribution. Geometric morphometric and morphological attributes of cells were used in combination with genetic analysis of the trnG ^ucc sequences of 30 strains isolated from a variety of European locations and obtained from culture collections. Micrasterias rotata proved to be phylogenetically homogenous across Europe while M. fimbriata turned out to be composed of two firmly delimited lineages, differing by molecular as well as by morphometric and morphological data. Published records of traditional M. fimbriata were also included in the classification discrimination analysis and were placed into the newly identified lineages upon comparison to the morphometric data collected from living material. Largely disparate geographic patterns were revealed within traditional M. fimbriata. One phylogenetic lineage is frequent in central and eastern Europe, but occurs also in the British Isles. A second lineage has been recorded in North America and in Western Europe, where its distribution is possibly limited to the west of the Rhine River. Interestingly, the morphometric analyses of the published records illustrated that the geographic differences have remained largely unchanged since the 1850s indicating a previously unknown distributional stability among microalgal species groups such as the desmids.     

Isolation and characterization of chitin from bumblebee (Bombus terrestris)

Insect chitin possessing shell-like structure was prepared from the bumblebee corpses by a consequent treatment with 1M HCl and 1M NaOH. The bumblebee chitin was compared with crustacean (shrimp) chitin by using elemental analysis, Fourier-transform infrared (FT-IR) and solid-state (13)C cross-polarization magic angle spinning nuclear magnetic resonance (CP/MAS)-NMR spectroscopy and confocal microscopy. Both chitins (bumblebee and shrimp) exhibited identical spectra, while the bumblebee chitin had a 5% lower degree of acetylation and was characterized by a fine membrane texture.     

Ion selectivity of a poly(3-pentylmethoxythiophene) LB-layer modified carbon-fiber microelectrode as a consequence of the second order filtering in voltcoulometry

Ion selective properties of poly(3-pentylmethoxythiophene) Langmuir-Blodgett film modified carbon-fiber microelectrode are described. The study of the electrode behavior indicates that important features occur if two electrochemical methods, one of them being kinetics sensitive, are used. While in case of the typical steady-state voltammetry the electrode remains sensitive to both the cations and anions, the kinetics-sensitive properties of voltcoulometry based on the second-order filtering scheme disable the observation of anions. As a model system a mixture of copper and dopamine ions is used.     

Assemblage structure and altitudinal distribution of lady beetles (Coleoptera,Coccinellidae) in the mountain spruce forests of Pol’ana Mountains,the West Carpathians

In two successive years we recorded a total of 3,636 individuals and 17 species of adult lady beetles (Coleoptera, Coccinellidae) in the spruce forests of Pol’ana Mts (the West Carpathians) at altitudes ranging from 600 m to 1,300 m a.s.l. Four lady beetle species were documented as predominating (dominance of abundance > 5%) over the study period. They were the following: Aphidecta obliterata (1,828 individuals and 50.3%), Coccinella septempunctata (634 individuals and 17.4%), Adalia conglomerata (594 individuals and 16.3%) and Anatis ocellata (279 individuals and 7.7%). The assemblages of lady beetles differed among the areas and also between the years. The season revealed neglegible effect on distribution of lady beetles, whereas the effect of altitude was more pronounced. A. conglomerata preferred the areas at lower altitude (600–725 m) to those at middle (900–925 m) and/or upper altitude (1,250–1,300 m). In contrast, A. obliterata and C. septempuctata were most abundant in the area at middle altitude. The altitudinal location of area partly explained the variability in abundance of lady beetles. The first ordination axis constructed by means of correspondence analysis (CA) represented an altitudinal gradient and accounted for 19.4% of the total variance of the species data. The great proportion of lady beetle species not typically associated with spruce and/or other coniferous trees than spruce (70.6%, n = 17) may be explained by an ecotonal effect.     

Biogas production: evaluation of the influence of K2FeO4 pretreatment of maple leaves (Acer platanoides) on microbial consortia composition

Bioprocess and Biosystems Engineering - The potential of K2FeO4 as a pretreatment agent of a lignocellulosic material was examined on leaves of Acer platanodides as the sole substrate for biogas...     

The adaptation responses of bacterial cytoplasmic membrane fluidity in the presence of environmental stress factors — polychlorinated biphenyls and 3-chlorobenzoic acid

Only bacteria sufficiently resistant to the toxic compounds in their environment can be used for the efficient biodegradation process in order to eliminate a widespread contamination by polychlorinated biphenyls (PCBs). The presence of PCBs results in bacterial controlled rigidification of cytoplasmic membrane. The four bacterial isolates from long-term PCB-contaminated soil (Alcaligenes xylosoxidans, Pseudomonas stutzeri) and sediment (Ochrobactrum anthropi, Pseudomonas veronii) have been used to select the strain most adapted to the PCBs, i.e. with efficient changes in the membrane phospholipid fatty acids. PCBs and their toxic degradation products — the 3-chlorobenzoic acids (3-CBA as the most toxic one) — were added separately to the liquid medium with glucose in two experimental sets: at lag phase and in stationary phase of bacterial growth in order to evaluate the effects of chemicals to cytoplasmic membrane. The main parameter — the changes in fatty acids composition (in the total lipids and the main membrane phospholipid phosphatidyletanolamine) were studied. 3-CBA caused growth inhibition when added at lag phase. However, when added during the stationary growth, inhibition was not observed. Similarly, after addition of PCBs to the stationary growth culture, inhibition of growth was not observed with all tested strains (except for P. stutzeri). This fact indicates the importance of time contact of bacteria during growth phase with xenobiotics. O. anthropi and A. xylosoxidans appeared to be the most adapted to the presence of PCBs (with sufficient membrane adaptation), active under the adverse conditions, and able to survive in the contaminated environment.     

Nuclear DNA content variation among perennial taxa of the genus Cyanus (Asteraceae) in Central Europe and adjacent areas

The genome size of 265 plants and the GC content of 126 plants from 63 populations of the Cyanus triumfetti and Cyanus montanus groups, collected across the Carpathians, Pannonia, Bohemian Massif, and Western and Dinaric Alps were determined by PI and DAPI flow cytometry. Variation of the nuclear DNA content among homoploid species, and intraspecific and interpopulation variation were confirmed in simultaneous analyses. The 2C-value at the diploid level (the C. triumfetti group) varied from 2.53 for Cyanus dominii subsp. sokolensis to 3.06?pg for C. triumfetti s.s. (1.21-fold range). At the tetraploid level (the C. montanus group), the 2C-value varied from 5.19 for Cyanus mollis to 5.84?pg for C. montanus (1.13-fold range). High intraspecific and interpopulation variation in the amount of nuclear DNA in the C. triumfetti group correlates with the extensive morphological variation found in this group. Significant between-species differences in genome size indicate that this attribute may be used as a supportive taxonomic marker for both of the groups studied. The GC content varied by 2.93?%, from 39.46?% for “Cyanus axillaris” to 40.61?% for Cyanus adscendens; this character is of no value for taxonomic purposes. Genome size of the studied populations is significantly higher in southern parts of the distribution area and at higher elevations. Plants with smaller genomes tend to occur in dry areas at low altitudes with high diurnal and annual temperature oscillations. The GC content of the populations studied is significantly correlated with longitude, increasing from east to west; and plants with GC-rich genomes are concentrated in the coldest areas with low minimum temperatures.