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581.
Katarína Valentovi
ov
ubica Halukov Jana Huttov Igor Mistrík Ladislav Tams 《Environmental and Experimental Botany》2009,66(3):457-462
The effect of Cd on oxalate oxidase (OxO) activity and its localisation were analysed in barley root. In Cd-treated roots OxO activity was strongly induced in the region 2–4 mm behind the root tip and in the area toward the root base. In situ analyses showed that Cd-induced OxO activity was localised to the cell wall (CW) of early metaxylem vascular bundles and surrounding parenchyma cells and was accompanied by lignification of metaxylem vessels. OxO activation was also observed during treatment with other heavy metals (HMs), salt treatment and at elevated non-optimal temperature. In contrast to HM activation of OxO and lignification, high temperature and NaCl indeed activated OxO but did not induce lignification of metaxylem vessels. These results suggest that oxalate oxidase as an H2O2-generating enzyme is activated in response to several stresses, however the ectopic lignification of metaxylem vessels is activated specifically by HMs. This HM-induced premature root xylogenesis due to ectopic lignification of metaxylem vessels probably causes shortening of the root elongation zone and therefore a reduction in root growth. 相似文献
582.
Miquel De Cáceres Milan Chytrý Emiliano Agrillo Fabio Attorre Zoltán Botta‐Dukát Jorge Capelo Bálint Czúcz Jürgen Dengler Jörg Ewald Don Faber‐Langendoen Enrico Feoli Scott B. Franklin Rosario Gavilán François Gillet Florian Jansen Borja Jiménez‐Alfaro Pavel Krestov Flavia Landucci Attila Lengyel Javier Loidi Ladislav Mucina Robert K. Peet David W. Roberts Jan Roleček Joop H.J. Schaminée Sebastian Schmidtlein Jean‐Paul Theurillat Lubomír Tichý Donald A. Walker Otto Wildi Wolfgang Willner Susan K. Wiser 《应用植被学》2015,18(4):543-560
583.
Ladislav Kov
Eva Bhmerov Peter Butko 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1982,721(4):341-348
Valinomycin and nigericin prevented growth of 13 strains of the yeast Saccharomyces cerevisiae on non-fermentable substrate glycerol without affecting much fermentative growth on glucose. The two antibiotics did not induce swelling and lysis of yeast protoplasts in potassium acetate and did not modify uptake and release of Rb+ by the yeast cells. Both antibiotics were taken up by yeast cells at a relatively low rate. Nigericin accelerated the glucose-induced changes of fluorescence of a cyanine dye absorbed by yeast cells, which had been previously ascribed to a depolarization-repolarization cycle of the mitochondrial membrane. The data suggest that valinomycin and nigericin act as ionophores in the inner mitochondrial membrane and not in the plasma membrane of intact yeast cells. 相似文献
584.
Abstract. In the framework of the European Vegetation Survey common data standards are proposed for recording phytosociological relevés for syntaxonomical classification. The authors wish to establish the notion that common data standards for recording phytosociological data can only be advantageous for advancing the credibility and application of vegetation science, and may stimulate other projects. 相似文献
585.
Nina S. Reuss Ladislav Hamerlík Gaute Velle Anders Michelsen Ole Pedersen Klaus P. Brodersen 《Hydrobiologia》2014,730(1):59-77
Most functional feeding types are represented within the species rich group of aquatic chironomids. Thus, we hypothesized that different lake types and microhabitats within lakes would (1) host specific chironomid communities and (2) that the individual communities would show specific δ 13C stable isotope signatures reflecting the prevailing origin of food source. To test our hypotheses, five lakes in southwest Greenland were investigated at a high taxonomic resolution and with detailed information on δ 13C signature of the chironomids and of individual microhabitats (macrophytes, sediment, stones, and profundal). We found that there was a significant difference in δ 13C between the chironomid assemblages of freshwater lakes and oligosaline lakes, while assemblages of the littoral microhabitats did not differ significantly. The δ 13C of chironomids reflected the wide variety of habitat signals, particularly in the freshwater lakes. Our results indicate that many chironomid taxa are ubiquitous and are found in several microhabitats, suggesting that they can adjust their feeding strategy according to the habitat. The implication is that chironomid assemblage composition has only limited use as indicator of littoral microhabitats in the Arctic. On the other hand, the δ 13C signature of fossil chironomids might have a potential as indicator of microhabitats in freshwater lakes. 相似文献
586.
Boris Sieger Karin Schubert Catriona Donovan Marc Bramkamp 《Molecular microbiology》2013,90(5):966-982
Lipid II flippases play an essential role in cell growth and the maintenance of cell shape in many rod‐shaped bacteria. The putative lipid II flippase RodA is an integral membrane protein and member of the SEDS (shape, elongation, division and sporulation) protein family. In contrast to its homologues in Escherichia coli and Bacillus subtilis little is known about the role of RodA in actinobacteria. In this study, we describe the localization and function of RodA in Corynebacterium glutamicum, a rod‐shaped, apically growing actinobacterium. RodA‐GFP localizes exclusively at the cell poles. Surprisingly, time‐lapse microscopy revealed that apical cell growth is sustained in a rodA deletion strain. However, growth rates and antibiotic susceptibility are altered. In the absence of RodA, it appears that apical growth is driven by lateral diffusion of lipid II that is likely flipped by the septal flippase, FtsW. Furthermore, we applied a previously described synthetic in vivo system in combination with FRET to identify an interaction between C. glutamicum RodA and the polar growth organizing protein DivIVA. 相似文献
587.
Ladislav Kümmel 《Bioscience reports》1983,3(7):643-646
Effeects of various ketogenic substrates on gluconeogenesis from lactate were examined. D,L-3-Hydroxybutyrate (5 mM) stimulated gluconeogenesis by 41%, the effect being the same as that of 5 mM acetate (49%). No stimulating effect of acetoacetate was observed; conversely, acetoacetate (up to 40 mM) partially or completely abolished the observed stimulating effects of acetate, oleate, and 3-hydroxybutyrate. The results suggest that, in intact liver cells, pyruvate is transported into mitochondria in exchange for acetoacetate and that an interrelationship between gluconeogenesis and ketogenesis at the level of mitochondrial pyruvate carrier may exist in the liver. 相似文献
588.
Paffetti D Vettori C Caramelli D Vernesi C Lari M Paganelli A Paule L Giannini R 《BMC evolutionary biology》2007,7(Z2):S6
Background
Phylogeographic analyses on the Western Euroasiatic Fagus taxa (F. orientalis, F. sylvatica, F. taurica and F. moesiaca) is available, however, the subdivision of Fagus spp. is unresolved and there is no consensus on the phylogeny and on the identification (both with morphological than molecular markers) of Fagus Eurasiatic taxa.For the first time molecular analyses of ancient pollen, dated at least 45,000 years ago, were used in combination with the phylogeny analysis on current species, to identify the Fagus spp. present during the Last Interglacial period in Italy.In this work we aim at testing if the trn L-trn F chloroplast DNA (cpDNA) region, that has been previously proved efficient in discriminating different Quercus taxa, can be employed in distinguishing the Fagus species and in identifying the ancient pollen.Results
86 populations from 4 Western Euroasistic taxa were sampled, and sequenced for the trn L-trn F region to verify the efficiency of this cpDNA region in identifying the Fagus spp.. Furthermore, Fagus crenata (2 populations), Fagus grandifolia (2 populations), Fagus japonica, Fagus hayatae, Quercus species and Castanea species were analysed to better resolve the phylogenetic inference.Our results show that this cpDNA region harbour some informative sites that allow to infer relationships among the species within the Fagaceae family. In particular, few specific and fixed mutations were able to discriminate and identify all the different Fagus species.Considering a short fragment of 176 base pairs within the trn L intron, 2 transversions were found able in distinguishing the F. orientalis complex taxa (F. orientalis, F. taurica and F. moesiaca) from the remaining Fagus spp. (F. sylvatica, F. japonica, F. hayataea, F. crenata and F. grandifolia). This permits to analyse this fragment also in ancient samples, where DNA is usually highly degraded.The sequences data indicate that the DNA recovered from ancient pollen belongs to the F. orientalis complex since it displays the informative sites characteristic of this complex.Conclusion
The ancient DNA sequences demonstrate for the first time that, in contrast to current knowledge based on palynological and macrofossil data, the F. orientalis complex was already present during the Tyrrhenian period in what is now the Venice lagoon (Italy).This is a new and important insight considering that nowadays West Europe is not the natural area of Fagus orientalis complex, and up to now nobody has hypothesized the presence during the Last Interglacial period of F. orientalis complex in Italy.589.
Bernard Poulain Ornella Rossetto Florence Deloye Giampietro Schiavo Ladislav Tauc Cesare Montecucco 《Journal of neurochemistry》1993,61(3):1175-1178
Abstract: The Shaw-type K+ channel Kv 3.1 was stably transfected in human embryonic kidney cells. Voltage dependence of activation, K+ permeability, sensitivity to external tetraethylammonium, and unitary conductance were similar to Kv 3.1 channels expressed transiently in Xenopus oocytes. Kv 3.1 channels appear to be regulated because the protein kinase C activator phorbol 12,13-dibutyrate decreased Kv 3.1 currents. Based on these results, we find that the stable expression of voltage-gated K+ channels in human embryonic kidney cells appears to be well suited for analysis of both biophysical and biochemical regulatory processes. 相似文献
590.
Tvrtko Korbar Ladislav Fuček Antun Husinec Igor Vlahović Nenad Oštrić Dubravko Matičec Vladimir Jelaska 《Facies》2001,45(1):39-58
Summary The island of Cres is located in the northern part of the Adriatic Sea. The island is built up of predominantly Cretaceous
carbonates deposited in north-western part of extensive and long-lasting Adriatic Carbonate Platform. Owing to the influence
of synsedimentary tectonics supported by eustatic changes during the latest Albian/Early Cenomanian, different sedimentary
environments were established: from shallow intraplatform basin and related slope, across basin margin to protected shallow-platform.
During the Early to Middle Cenomanian rudist communities (ichthyosarcolitid/caprinid/radiolitid)flourished along a relatively
high-energy intraplatform basin margin. Fair amounts of coarse-grained bioclasts, derived almost exclusively from broken rudist
shells, were deposited over a marginal depocenter. Contemporaneously, pithonellid wackestone-packstones containing microbioclasts
and planktonic foraminifera were deposited basinward while marginal bioclastic sediments and limestone blocks of the basin
margin origin were sporadically deposited within the basin. The opening of the Cres intraplatform basin was aborted and the
basin was finally filled up during the Late Cenomanian. Since the Cres intraplatform basin was established at the beginning
of the Cenomanian it probably represented the initiation phase in the north-western extension of the later Adriatic Trough
development. 相似文献