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51.
The DcMaster Transposon Display maps polymorphic insertion sites in the carrot (Daucus carota L.) genome 总被引:2,自引:0,他引:2
DcMaster is a family of PIF/Harbinger-like class II transposable elements identified in carrot. We present a modified Transposon Display molecular marker system allowing amplification of genomic regions containing DcMaster elements. We scored 77 DcMaster Transposon Display (DcMTD) amplicons, of which 54 (70%) were segregating in the F2 progeny from the cross between wild and cultivated carrot. Segregating amplicons were incorporated into a previously developed molecular linkage map of carrot. Twenty-eight markers were attributed to the wild parent, 23 originated from the cultivated parent, and three markers remained unlinked. The markers were evenly distributed among the nine linkage groups. However, differences in the distribution pattern of DcMaster insertion sites in the genomes of the wild and cultivated parent were observed. Specificity of the obtained amplicons was confirmed by sequencing and three putative DcMaster subfamilies, differing in the sequence of their terminal inverted repeats, were revealed. 相似文献
52.
This work is a continuation of earlier research concerning the influence of tin compounds on the dynamic properties of liposome membranes produced with lecithin hen egg yolks (EYL). The experiments were carried out at room temperature (about 25 degrees C). Four tin compounds were chosen, including three organic ones, (CH3)4Sn, (C2H5)4Sn and (C3H7)3SnCl, and one inorganic, SnCl2. The investigated compounds were admixed to water dispersions of liposomes. The content of the admixture changed within the range 0 mol-% to 11mol-% in proportion to EYL. Two spin probes were used in the experiment: 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and 2-ethyl-2-(15-methoxy-15-oxopentadecyl)-4,4-dimethyl-3-oxazolidinyloxyl (16-DOXYL-stearic acid), which penetrated through different areas of the membrane. It was found that tin compounds containing chlorine were the most active in interaction with liposome membranes. In the case of (C3H7)3SnCl, after exceeding 4% admixture content, an additional line appeared in the spectrum of the TEMPO probe which can be a result of formation of domain structures in the membranes of the studied liposomes. Compounds containing chlorine are of ionized form in water solution. The obtained results can thus mean that the activity of admixtures can be seriously influenced by their ionic character. In case of an admixture of non-ionic compounds the compound with a longer hydrocarbon chain displayed a slightly stronger effect on the spectroscopic parameters of the probes. 相似文献
53.
Quantification of Alternaria,Cladosporium, Fusarium and Penicillium verrucosum in Conventional and Organic Grains by qPCR 下载免费PDF全文
We analysed the levels of Alternaria, Cladosporium, Fusarium and Penicillium verrucosum in grain samples harvested in 2011 and 2012 from conventional and organic farms using qPCR. In general, both Alternaria and Cladosporium occurred in all cereal grains in the highest quantities, followed by P. verrucosum and Fusarium. Alternaria, Cladosporium and P. verrucosum had the highest levels in crop mixtures, barley and rye and lower levels in wheat, while Fusarium levels were the highest in crop mixtures and wheat. The levels of Alternaria and P. verrucosum were higher in organic rye and wheat than conventional grains. Although the level of Fusarium was higher in conventional than organic rye, opposite results were obtained for crop mixtures. A positive correlation was found between Alternaria, Cladosporium and P. verrucosum, indicating that similar factors might affect the distribution of these fungi in grains. 相似文献
54.
55.
Dariusz Man Rudolf Słota Małgorzata A. Broda Giuseppe Mele Jun Li 《Journal of biological inorganic chemistry》2011,16(1):173-181
Liposomes characterized by membranes featuring diverse fluidity (liquid-crystalline and/or gel phase), prepared from egg yolk
lecithin (EYL) and dipalmitoylphosphatidylcholine (DPPC), were doped with selected metalloporphyrins and the time-related
structural and dynamic changes within the lipid double layer were investigated. Porphyrin complexes of Mg(II), Mn(III), Fe(III),
Co(II), Ni(II), Cu(II), Zn(II), and the metal-free base were embedded into the particular liposome systems and tested for
350 h at 24°C using the electron spin resonance (ESR) spin probe technique. 5-DOXYL, 12-DOXYL, and 16-DOXYL stearic acid methyl
ester spin labels were applied to explore the interior of the lipid bilayer. Only the 16-DOXYL spin probe detected evident
structural changes inside the lipid system due to porphyrin intercalation. Fluidity of the lipid system and the type of the
porphyrin complex introduced significantly affected the intermolecular interactions, which in certain cases may result in
self-assembly of metalloporphyrin molecules within the liposome membrane, reflected in the presence of new lines in the relevant
ESR spectra. The most pronounced time-related effects were demonstrated by the EYL liposomes (liquid-crystalline phase) when
doped with Mg and Co porphyrins, whereas practically no spectral changes were revealed for the metal-free base and both the
Ni and Zn dopants. ESR spectra of the porphyrin-doped gel phase of DPPC liposomes did not show any extra lines; however, they
indicated the formation of a more rigid lipid medium. Electronic configuration of the porphyrin’s metal center appeared crucial
to the degree of molecular reorganization within the phospholipid bilayer system. 相似文献
56.
57.
Chatterjee P Basu S Kundu M Nasipuri M Plewczynski D 《Journal of molecular modeling》2011,17(9):2191-2201
Secondary structure prediction is a crucial task for understanding the variety of protein structures and performed biological
functions. Prediction of secondary structures for new proteins using their amino acid sequences is of fundamental importance
in bioinformatics. We propose a novel technique to predict protein secondary structures based on position-specific scoring
matrices (PSSMs) and physico-chemical properties of amino acids. It is a two stage approach involving multiclass support vector
machines (SVMs) as classifiers for three different structural conformations, viz., helix, sheet and coil. In the first stage, PSSMs obtained from PSI-BLAST and five specially selected physicochemical properties
of amino acids are fed into SVMs as features for sequence-to-structure prediction. Confidence values for forming helix, sheet and coil that are obtained from the first stage SVM are then used
in the second stage SVM for performing structure-to-structure prediction. The two-stage cascaded classifiers (PSP_MCSVM) are trained with proteins from RS126 dataset. The classifiers
are finally tested on target proteins of critical assessment of protein structure prediction experiment-9 (CASP9). PSP_MCSVM
with brainstorming consensus procedure performs better than the prediction servers like Predator, DSC, SIMPA96, for randomly
selected proteins from CASP9 targets. The overall performance is found to be comparable with the current state-of-the art. PSP_MCSVM source code, train-test datasets and supplementary files are available freely in public domain at: and 相似文献
58.
Latowski D Kuczyńska P Strzałka K 《Redox report : communications in free radical research》2011,16(2):78-90
Six different xanthophyll cycles have been described in photosynthetic organisms. All of them protect the photosynthetic apparatus from photodamage caused by light-induced oxidative stress. Overexcitation conditions lead, in the chloroplast, to the over-reduction of the NADP pool and production of superoxide, which can subsequently be metabolized to hydrogen peroxide or a hydroxyl radical, other reactive oxygen species (ROS). On the other hand, overexcitation of photosystems leads to an increased lifetime of the chlorophyll excited state, increasing the probability of chlorophyll triplet formation which reacts with triplet oxygen forming single oxygen, another ROS. The products of the light-dependent phase of xanthophyll cycles play an important role in the protection against oxidative stress generated not only by an excess of light but also by other ROS-generating factors such as drought, chilling, heat, senescence, or salinity stress. Four, mainly hypothetical, mechanisms explaining the protective role of xanthophyll cycles in oxidative stress are presented. One of them is the direct quenching of overexcitation by products of the light phase of xanthophyll cycles and three others are based on the indirect participation of xanthophyll cycle carotenoids in the process of photoprotection. They include: (1) indirect quenching of overexcitation by aggregation-dependent light-harvesting complexes (LHCII) quenching; (2) light-driven mechanisms in LHCII; and (3) a model based on charge transfer quenching between Chl a and Zx. Moreover, results of the studies on the antioxidant properties of xanthophyll cycle pigments in model systems are also presented. 相似文献
59.
Beata Olas Joanna Kołodziejczyk-Czepas Barbara Wachowicz Dariusz Jędrejek Anna Stochmal Wiesław Oleszek 《Central European Journal of Biology》2011,6(6):990-996
Humulus lupulus (Cannabaceae) is well known throughout the world as a raw material in the brewing industry. The antioxidative action of hop cones is poorly
understood, therefore the aim of our present study was to investigate in vitro changes in human plasma induced by peroxynitrite in the presence of the highly purified extract from hop cones (Humulus lupulus). The aim of our study was also to explain the effect of the extract from hop cones on coagulation activity of human plasma
treated with peroxynitrite. The action of the extract from hop cones was compared with the properties of a well-characterized
commercial monomeric polyphenol — resveratrol (3,4′,5-trihydroxystilbene). The tested plant extract, like resveratrol, significantly
inhibited protein carbonylation and nitration in plasma treated with ONOO−(0.1 mM). The extract from hop cones, like resveratrol, also caused a distinct reduction of plasma lipid peroxidation induced
by ONOO−. Moreover, the tested extract modulated the coagulation properties of plasma treated with peroxynitrite. It seems that antioxidative
activities of the highly purified extract from hop cones may be responsible for its medicinal properties. 相似文献
60.
The effect of cadmium and zinc ions on violaxanthin cycle enzymes, violaxanthin de-epoxidase and zeaxanthin epoxidase, has been investigated on selected plant species, as well as in vitro. About 50% inhibition of zeaxanthin epoxidase by cadmium ions was found for duckweed (Lemna trisulca) and tomato (Lycopersicon esculentum) leaves but for apricot (Prunus armeniaca) leaves no cadmium inhibition of the epoxidation reaction was observed. The cadmium inhibition of zeaxanthin epoxidase in tomato was abolished by zinc ions. Zinc ions alone did not affect the activity of neither of the enzymes of the violaxanthin cycle. This suggests that mechanism of cadmium inactivation of the enzyme relies on cadmium interaction with a cysteine residue of the protein, important for the enzyme activity. The target cysteine in tomato epoxidase could be the cysteine residue present in the most conservative part of the molecule which is not present in the apricot enzyme sequence. Neither stimulation nor inhibition of violaxanthin de-epoxidase by cadmium ions both in vivo and in vitro studies was detected. It confirms the proposed mechanism of zeaxanthin epoxidation inhibition by cadmium ions because the cysteine residue in the conservative motif of violaxathin de-epoxidase is not present. 相似文献