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61.
Promnares K Komenda J Bumba L Nebesarova J Vacha F Tichy M 《The Journal of biological chemistry》2006,281(43):32705-32713
Cyanobacteria contain several genes coding for small one-helix proteins called SCPs or HLIPs with significant sequence similarity to chlorophyll a/b-binding proteins. To localize one of these proteins, ScpD, in the cells of the cyanobacterium Synechocystis sp. PCC 6803, we constructed several mutants in which ScpD was expressed as a His-tagged protein (ScpDHis). Using two-dimensional native-SDS electrophoresis of thylakoid membranes or isolated Photosystem II (PSII), we determined that after high-light treatment most of the ScpDHis protein in a cell is associated with PSII. The ScpDHis protein was present in both monomeric and dimeric PSII core complexes and also in the core subcomplex lacking CP43. However, the association with PSII was abolished in the mutant lacking the PSII subunit PsbH. In a PSII mutant lacking cytochrome b(559), which does not accumulate PSII, ScpDHis is associated with CP47. The interaction of ScpDHis with PsbH and CP47 was further confirmed by electron microscopy of PSII labeled with Ni-NTA Nanogold. Single particle image analysis identified the location of the labeled ScpDHis at the periphery of the PSII core complex in the vicinity of the PsbH and CP47. Because of the fact that ScpDHis did not form any large structures bound to PSII and because of its accumulation in PSII subcomplexes containing CP47 and PsbH we suggest that ScpD is involved in a process of PSII assembly/repair during the turnover of pigment-binding proteins, particularly CP47. 相似文献
62.
Limonium failachicum, a new diploid (2n=18) species ofPlumbaginaceae, is described from Arabia. The species is taxonomically related toL. iranicum andL. carnosum. The new taxon is so far the only known endemic species for the State of Kuwait. Ecology and distribution of the new species is briefly discussed. 相似文献
63.
Ladislav Tamás Beáta Bočová Jana Huttová Igor Mistrík Marta Ollé 《Plant Growth Regulation》2006,48(1):41-49
The effect of excess cadmium (Cd: 0.0, 0.25, 0.5, 1.0 and 2.0 mM) on growth and ascorbate oxidase (AO) activity was investigated
in barley (Hordeum vulgare L. cv. Jubilant) roots. The study employed a filter-paper technique to germinate and grow the germinating seeds following
imbibition with respective Cd treatments for 4 h at 25 °C in darkness. Cd was required at 1.0 mM to affect 50% root growth
inhibition 72 h after the treatment. This Cd-induced root growth inhibition was accompanied by a corresponding loss of plasma
membrane integrity in root cells as evaluated by Evans blue uptake. Excess Cd (1.0 and 2.0 mM) significantly inhibited the
AO activity in all the analysed fractions of barley roots such as extracellular, soluble, cell wall (CW)- and membrane-bound
fractions. AO was localized in the apoplast, and its highest specific activity was detected in the CW II fraction obtained
by extraction with 1.0 M NaCl from purified cell walls. The analysis of AO isozyme profile showed that besides the reduced
activity of two anionic and two cationic isozymes, one cationic AO isozyme was activated during excess Cd treatment, which
could be detected in cell wall fractions CW II, III and IV. 相似文献
64.
65.
Magri D Vendramin GG Comps B Dupanloup I Geburek T Gömöry D Latałowa M Litt T Paule L Roure JM Tantau I van der Knaap WO Petit RJ de Beaulieu JL 《The New phytologist》2006,171(1):199-221
Here, palaeobotanical and genetic data for common beech (Fagus sylvatica) in Europe are used to evaluate the genetic consequences of long-term survival in refuge areas and postglacial spread. Four large datasets are presented, including over 400 fossil-pollen sites, 80 plant-macrofossil sites, and 450 and 600 modern beech populations for chloroplast and nuclear markers, respectively. The largely complementary palaeobotanical and genetic data indicate that: (i) beech survived the last glacial period in multiple refuge areas; (ii) the central European refugia were separated from the Mediterranean refugia; (iii) the Mediterranean refuges did not contribute to the colonization of central and northern Europe; (iv) some populations expanded considerably during the postglacial period, while others experienced only a limited expansion; (v) the mountain chains were not geographical barriers for beech but rather facilitated its diffusion; and (vi) the modern genetic diversity was shaped over multiple glacial-interglacial cycles. This scenario differs from many recent treatments of tree phylogeography in Europe that largely focus on the last ice age and the postglacial period to interpret genetic structure and argue that the southern peninsulas (Iberian, Italian and Balkan) were the main source areas for trees in central and northern Europe. 相似文献
66.
Il’ja Krno Ferdinand Šporka Joanna Galas Ladislav Hamerlík Zuzana Zaťovičová Peter Bitušík 《Biologia》2006,61(18):S147-S166
Littoral benthic macroinvertebrates of 45 mountain lakes in the Tatra Mountains were sampled using a semi-quantitative method in September 2000. A total of 32,852 specimens were identified to 93 taxa belonging to 14 higher taxonomic groups. Multivariate statistics (CCA, RDA) and nine biotic metrics (AQEM/STAR) were used to explain relationships between macroinvertebrate assemblages and environmental variables. Up to 57% of the ecological position of littoral macroinvertebrate assemblages were explained by variance of environmental variables divided into chemical, trophic, physical, catchment and location. Five types of Tatra lakes were recognized using CCA: A — strongly acidified lakes (small catchment, low pH, high concentration of TP, DOC, highest amount of POM in littoral); B — alpine acidified lakes (low amount of POM, low values of biotic metrics); C — alpine non-acidified lakes (high value of diversity index, predominance of Diptera); D — subalpine acidified lakes (high values of biotic metrics: number of families, proportion of crenal and rhithral taxa/total taxa); E — subalpine non-acidified lakes (high values of biotic metrics: number of families, number of genera, BMWP score, number of taxa and abundance of EPT taxa). RDA was used to design five levels of macroinvertebrate taxa acidification tolerance. The Tatra Acidification Index (TAI) was established to assess the acidification status of the lakes in the Tatra Mts. 相似文献
67.
Ladislav Roller 《Biologia》2006,61(2):193-205
Species representation and seasonality of adult sawflies (Symphyta) were studied using Malaise traps at three submontane study
sites (Hriňová — HR, Mošovce — MO and Štefanová — ŠT) in the Western Carpathians (Central Slovakia). One trap was operated
at each study site continuously during the growing season, in MO in 1992, in HR in 1995 and in ŠT in 1996. A total of 9,281
adults representing 244 species in 9 families were collected. Very rich sawfly assemblages were found. The highest species
richness was in MO (181 species), followed by ŠT (153 species) and HR (118 species). Pseudodineura fuscula was recorded from Slovakia for the first time. Adults were present in traps from the end of April through the first half
of October. Most species occurred from the second half of May through the first half of June and finished flight activity
by the end of June. Seasonal flight activities of the 16 most abundant species are analysed and discussed. 相似文献
68.
A new cryopreservation method using perlite as a carrier was evaluated on a large set of mycelial cultures of basidiomycetes. The viability and some other characteristics--growth, macro- and micromorphology, and laccase production--of 442 strains were tested after 48-h and then after 3-year storage in liquid nitrogen using a perlite protocol (PP). All (100%) of them survived successfully both 48-h storage and 3-year storage in liquid nitrogen without noticeable growth and morphological changes. Also laccase production was unchanged. The viability and laccase production of a part (250) of these strains were compared with those of the strains subjected to an original agar plug protocol (OP). Using OP, 144 strains (57.6%) out of 250 survived a 3-year storage in liquid nitrogen. The results indicate that the cryopreservation protocol used significantly influences survival of the strains. Markedly better results were achieved using the PP. 相似文献
69.
We evaluated the ability of alpha-tocopheryl succinate (alpha-TOS) to sensitise TRAIL-resistant malignant mesothelioma (MM) cells to TRAIL-induced apoptosis. We show that alpha-TOS activates expression of DR4/DR5 in a p53-dependent manner and re-establishes sensitivity of resistant MM cells to TRAIL-mediated apoptosis, as documented in p53wt MM cells but not in their p53null counterparts. MM cells selected for TRAIL resistance expressed low cell surface levels of DR4 and DR5. Treatment with sub-lethal doses of alpha-TOS restored expression of DR4 and DR5. The ability of alpha-TOS to modulate expression of pro-apoptotic genes may play a role in sensitisation of tumour cells to immunological stimuli. 相似文献
70.
L’ubica Liptáková Beáta Bo?ová Jana Huttová Igor Mistrík Ladislav Tamás 《Plant cell reports》2012,31(12):2189-2197