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811.
Árvay Július Šnirc Marek Hauptvogl Martin Bilčíková Jana Bobková Alica Demková Lenka Hudáček Marek Hrstková Miroslava Lošák Tomáš Král Martin Kováčik Anton Štefániková Jana 《Biological trace element research》2019,190(1):226-233
Biological Trace Element Research - The aim of the present study was to determine concentrations of 15 macro- and micro-elements in 10 commercially available plantation Arabica coffee brands. The... 相似文献
812.
813.
Katerina Zabrady Marek Adamus Lucie Vondrova Chunyan Liao Hana Skoupilova Marketa Novakova Lenka Jurcisinova Aaron Alt Antony W. Oliver Alan R. Lehmann Jan J. Palecek 《Nucleic acids research》2016,44(3):1064-1079
SMC5/6 is a highly conserved protein complex related to cohesin and condensin, which are the key components of higher-order chromatin structures. The SMC5/6 complex is essential for proliferation in yeast and is involved in replication fork stability and processing. However, the precise mechanism of action of SMC5/6 is not known. Here we present evidence that the NSE1/NSE3/NSE4 sub-complex of SMC5/6 binds to double-stranded DNA without any preference for DNA-replication/recombination intermediates. Mutations of key basic residues within the NSE1/NSE3/NSE4 DNA-binding surface reduce binding to DNA in vitro. Their introduction into the Schizosaccharomyces pombe genome results in cell death or hypersensitivity to DNA damaging agents. Chromatin immunoprecipitation analysis of the hypomorphic nse3 DNA-binding mutant shows a reduced association of fission yeast SMC5/6 with chromatin. Based on our results, we propose a model for loading of the SMC5/6 complex onto the chromatin. 相似文献
814.
Nezbedová Lenka Hesse Manfred Dušek Jaroslav Werner Christa 《Plant Cell, Tissue and Organ Culture》1999,58(2):133-140
Six different callus lines and three different suspension culture lines were established from plants of two Aphelandra species (Acanthaceae). All established lines were analyzed for secondary metabolite accumulation. A discrepancy between secondary
metabolites accumulated in the plants and in the cell cultures could be observed. All established Aphelandrasp. cell cultures produced verbascoside (acteoside) as the major extractable metabolite. Time course experiments were carried
out to investigate the relationship between cell growth and verbascoside production. In the present study it was shown that
verbascoside accumulation was growth dependent and positively related to the presence of 2,4-D in the medium. The conditions
in which verbascoside represents ca. 18% of cell culture weight have been defined. Free polyamines were detected in the cell
culture lines cultivated in MS liquid medium (cysteine 10 mg l-1, thiamine 1 mg l-1, 2,4-D 1 mg l-1, kinetin 0.2 mg l-1 and sucrose 30 g l-1). Putrescine and spermidine accumulated within 8 days to a maximum of 8.4 μmol g-1 of dry wt and 2.6 μmol g-1 of dry wt respectively and thereafter their concentration decreased rapidly. There was no evidence for the presence of spermine
or any other type of free or conjugated polyamines in the tested cell culture lines.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
815.
816.
Phylogenetic hypotheses of the relationships of Diptera: Anthomyzidae (61 taxa) are discussed with special reference to the genera Fungomyza Rohá?ek, 1999, Anthomyza Fallén, 1810, Epischnomyia Rohá?ek, 2006 and Arganthomyza Rohá?ek, 2009 based on the analysis of 7 combined mitochondrial + nuclear gene markers in comparison with results of the most recent cladistic analysis of morphological characters. The majority of revealed inter‐ and intrageneric relationships of these genera in both analyses were largely congruent except for the topology of Fungomyza and Arganthomyza being equivocal because of different topologies in phylograms generated by alternative molecular methods and Epischnomyia forming a branch within Anthomyza in the molecular data hypothesis. The formerly unsettled Anthomyza drachma proved to be the sister species of the A. umbrosa group while the affinity of A. flavosterna to the A. bellatrix group has not been confirmed. The first phylogenetic hypothesis of Anthomyzinae to include timing of the nodes of divergence is presented. The origin of the subfamily is dated into the Eocene, ca 37.5 (30.6 – 45.3) MYA, and agrees with the age of the oldest known fossils from Baltic amber. The analysed members of the Anthomyza group of genera were found to have already evolved in the upper Oligocene. The divergences of the Palaearctic and Nearctic sister species in Arganthomyza and Anthomyza were found to occur at several different times during the Neogene (upper Miocene) to lower Quaternary (Pleistocene), from about 7 to 0.7 MYA. These were likely the result of fragmentation of widespread (Holarctic or Sino‐Japanese–Nearctic) ranges of ancestral taxa by vicariance events that were, in turn, caused by multiple interruptions of Beringia Land Bridges or cooling of climate and seem to be consistent with the times of multiple disjunctions of the flora. 相似文献
817.
Sebela Marek; Luhov Lenka; Frbort Ivo; Hirota Shun; Faulhammer Heinz G.; Stuzka Vclav; Pec Pave 《Journal of experimental botany》1997,48(11):1897-1907
Amine oxidase from etiolated seedlings of fenugreek (Trigonellafoenumgraecum) has been isolated by a purification procedureinvolving three chromatographic steps. The homogeneousenzyme is of pink colour with a visible absorption maximum at500 nm. The dimeric enzyme (2 75 kDa) is a slightly acidicprotein (pl 6.8) containing 8% neutral sugars. Nterminalamino acid sequence of the enzyme shows a high degree of similarityto other plant and microbial coppercontaining amine oxidases.The best substrates of the enzyme are aliphatic diamines andsome polyamines, whereas inhibitors are substrate analogues,copper complexing agents, some alkaloids and several other compounds.Spectrophotometric titrations with phenylhydrazines demonstratedone reactive carbonyl group per subunit of the enzyme and redoxcyclicquinone staining after native electrophoresis indicatedthe presence of a quinone cofactor. Differential pulse polarographyshowed the existence of a copper/quinonecontaining activesite. The resonance Raman spectroscopy and the pHdependentshift of the absorption spectrum of the enzyme pnitrophenylhydrazoneconfirm unambiguously the identity of the cofactor with topaquinone. EPR spectra of the enzyme are in accordance with thoseof tetragonal cupric complexes as known for other coppercontainingamine oxidases. Besides the copper, Mn(II)ions were detectedthat partially occupy another metal site in the enzyme, buttheir catalytical importance is unlikely. Key words: Fenugreek, Trigonella foenumgraceum, amine oxidase, topa quinone 相似文献