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991.
Lisec J Römisch-Margl L Nikoloski Z Piepho HP Giavalisco P Selbig J Gierl A Willmitzer L 《The Plant journal : for cell and molecular biology》2011,68(2):326-336
We conducted a comparative analysis of the root metabolome of six parental maize inbred lines and their 14 corresponding hybrids showing fresh weight heterosis. We demonstrated that the metabolic profiles not only exhibit distinct features for each hybrid line compared with its parental lines, but also separate reciprocal hybrids. Reconstructed metabolic networks, based on robust correlations between metabolic profiles, display a higher network density in most hybrids as compared with the corresponding inbred lines. With respect to metabolite level inheritance, additive, dominant and overdominant patterns are observed with no specific overrepresentation. Despite the observed complexity of the inheritance pattern, for the majority of metabolites the variance observed in all 14 hybrids is lower compared with inbred lines. Deviations of metabolite levels from the average levels of the hybrids correlate negatively with biomass, which could be applied for developing predictors of hybrid performance based on characteristics of metabolite patterns. 相似文献
992.
M. Tahir Waheed Nadja Thönes Martin Müller S. Waqas Hassan N. Mona Razavi Elke Lössl Hans-Peter Kaul Andreas G. Lössl 《Transgenic research》2011,20(2):271-282
Certain types of human papillomaviruses (HPV) are causatively associated with cervical carcinoma, the second most common cancer
in women worldwide. Due to limitations in the availability of currently used virus-like particle (VLP)-based vaccines against
HPV to women of developing countries, where most cases of cervical cancer occur, the development of a cost-effective second-generation
vaccine is a necessity. Capsomeres have recently been demonstrated to be highly immunogenic and to have a number of advantages
as a potential cost-effective alternative to VLP-based HPV vaccines. We have expressed a mutated HPV-16 L1 (L1_2xCysM) gene
that retained the ability to assemble L1 protein to capsomeres in tobacco chloroplasts. The recombinant protein yielded up
to 1.5% of total soluble protein. The assembly of capsomeres was examined and verified by cesium chloride density gradient
centrifugation and sucrose sedimentation analysis. An antigen capture enzyme-linked immunosorbent assay confirmed the formation
of capsomeres by using a conformation-specific monoclonal antibody which recognized the conformational epitopes. Transplastomic
tobacco plants exhibited normal growth and morphology, but all such lines showed male sterility in the T0, T1 and T2 generations. Taken together, these results indicate the possibility of producing a low-cost capsomere-based vaccine by plastids. 相似文献
993.
Rhodoferax-related pufM gene cluster dominates the aerobic anoxygenic phototrophic communities in German freshwater lakes 总被引:1,自引:0,他引:1
The presence of aerobic anoxygenic phototrophs (AAPs) has been repeatedly reported from various marine environments, but their distribution in freshwater lakes was neglected until recently. We investigated the phylogenetic composition of AAP communities in 10 lakes in Northeastern Germany with different trophic status including oligotrophic Lake Stechlin and humic matter rich Lake Grosse Fuchskuhle. The AAP community was composed by members of Alpha- and Betaproteobacteria, but their contribution varied largely among the studied lakes. Our results show that AAP community composition in the studied lakes was affected mostly by pH and humic matter content. While alkaline lakes were mostly composed of Betaproteobacteria, the acidic and humic matter rich south-west (SW) basin of Lake Grosse Fuchskule was dominated (87%) by Alphaproteobacteria. The most frequent group within Betaproteobacteria was a cluster of pufM genes which was phylogenetically related to Rhodoferax representing 38.5% of all retrieved sequences. Alphaproteobacteria-related sequences had a broader phylogenetic diversity including six different taxa dominated by Sphingomonas- and Rhodobacter-like bacteria in lakes with alkaline to neutral pH. In the acidic and humic matter-rich SW basin of Lake Grosse Fuchskuhle, however, Methylobacterium-related sequences dominated the AAP community. We suggest that the variable AAP community structure might reflect the potential of these bacteria to cope with the contrasting conditions in freshwater environments. 相似文献
994.
995.
Vödisch M Scherlach K Winkler R Hertweck C Braun HP Roth M Haas H Werner ER Brakhage AA Kniemeyer O 《Journal of proteome research》2011,10(5):2508-2524
996.
Field D Amaral-Zettler L Cochrane G Cole JR Dawyndt P Garrity GM Gilbert J Glöckner FO Hirschman L Karsch-Mizrachi I Klenk HP Knight R Kottmann R Kyrpides N Meyer F San Gil I Sansone SA Schriml LM Sterk P Tatusova T Ussery DW White O Wooley J 《PLoS biology》2011,9(6):e1001088
A vast and rich body of information has grown up as a result of the world's enthusiasm for 'omics technologies. Finding ways to describe and make available this information that maximise its usefulness has become a major effort across the 'omics world. At the heart of this effort is the Genomic Standards Consortium (GSC), an open-membership organization that drives community-based standardization activities, Here we provide a short history of the GSC, provide an overview of its range of current activities, and make a call for the scientific community to join forces to improve the quality and quantity of contextual information about our public collections of genomes, metagenomes, and marker gene sequences. 相似文献
997.
SDS normally is strictly avoided during Blue native (BN) PAGE because it leads to disassembly of protein complexes and unfolding of proteins. Here, we report a modified BN-PAGE procedure, which is based on low-SDS treatment of biological samples prior to native gel electrophoresis. Using mitochondrial OXPHOS complexes from Arabidopsis as a model system, low SDS concentrations are shown to partially dissect protein complexes in a very defined and reproducible way. If combined with 2-D BN/SDS-PAGE, generated subcomplexes and their subunits can be systematically investigated, allowing insights into the internal architecture of protein complexes. Furthermore, a 3-D BN/low-SDS BN/SDS-PAGE system is introduced to facilitate structural analysis of individual protein complexes without their previous purification. 相似文献
998.
Tatjana?M. Hildebrandt Ivano Di Meo Massimo Zeviani Carlo Viscomi Hans-Peter Braun 《Bioscience reports》2013,33(4)
Hydrogen sulfide is a physiologically relevant signalling molecule. However, circulating levels of this highly biologically active substance have to be maintained within tightly controlled limits in order to avoid toxic side effects. In patients suffering from EE (ethylmalonic encephalopathy), a block in sulfide oxidation at the level of the SDO (sulfur dioxygenase) ETHE1 leads to severe dysfunctions in microcirculation and cellular energy metabolism. We used an Ethe1-deficient mouse model to investigate the effect of increased sulfide and persulfide concentrations on liver, kidney, muscle and brain proteomes. Major disturbances in post-translational protein modifications indicate that the mitochondrial sulfide oxidation pathway could have a crucial function during sulfide signalling most probably via the regulation of cysteine S-modifications. Our results confirm the involvement of sulfide in redox regulation and cytoskeleton dynamics. In addition, they suggest that sulfide signalling specifically regulates mitochondrial catabolism of FAs (fatty acids) and BCAAs (branched-chain amino acids). These findings are particularly relevant in the context of EE since they may explain major symptoms of the disease. 相似文献
999.
Jeremy P.E. Spencer Gunter G.C. Kuhnle Mohamad Hajirezaei Hans-Peter Mock Uwe Sonnewald Catherine Rice-Evans 《Free radical research》2013,47(9):1005-1016
There is increasing interest in the ability of diets rich in polyphenols to modulate age-related diseases and promote healthy ageing. We have conducted a pilot experiment with eight tomato varieties to correlate the total antioxidant capacity of the tomato variants with the specific constituent flavonoids present. A strong correlation was observed with the flavonol rhamnoglucoside rutin but not with other flavonoids, such as naringenin chalcone, or hydroxycinnamates, such as chlorogenic, which are also present in the tomato. To test the rigor of this correlation a second study was undertaken with a further 37 tomato varieties selected for low, medium and high rutin levels. We show that the flavonol rutin contributes to the greatest extent to the antioxidant capacity of tomatoes and suggest that this flavonoid may be a useful target for up-regulation in tomatoes in order to improve their antioxidant status. 相似文献
1000.
Immunological detection of tonoplast polypeptides in the plasma membrane of pea cotyledons 总被引:7,自引:0,他引:7
David G. Robinson Hans-Peter Haschke Giselbert Hinz Birgit Hoh Masayoshi Maeshima Francis Marty 《Planta》1996,198(1):95-103
The tonoplast is usually characterized by the presence of two electrogenic proton pumps: a vacuolartype H+-ATPase and a pyrophosphatase, as well as a putative water-channel-forming protein (γ-TIP). Using a post-embedding immunogold labelling technique, we have detected the presence of these transport-protein complexes not only in the tonoplast, but also in the plasma membrane and trans Golgi elements of maturing pea (Pisum sativum L.) cotyledons. These ultrastructural observations are supported by Western blotting with highly purified plasma-membrane fractions. In contrast to the vacuolar-type H+-ATPase, whose activity was not measurable, considerable pyrophosphatase activity was detected in the plasma-membrane fraction. These results are discussed in terms of a possible temporary repository for tonoplast proteins en route to the vacuole. 相似文献