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221.
Sphagnum farming In Germany, 99% of the 1.4 Mha of peatlands have been drained for land use. These degraded areas release enormous amounts of greenhouse gases. In contrast, land use on rewetted peatlands (= paludiculture) not only avoids greenhouse gas emissions, but offers numerous additional environmental benefits, while maintaining biomass production. Field studies have demonstrated the additional benefits of peatmoss (Sphagnum) cultivation for plant and animal diversity. After harvesting of the upper moss layer, the biomass is prepared to be used as a substitute for peat in horticultural substrates. Sphagnum farming is a promising and sustainable land use alternative for degraded bog areas.  相似文献   
222.

Objectives

To use permeabilized cells of the fission yeast, Schizosaccharomyces pombe, that expresses human UDP-glucose 6-dehydrogenase (UGDH, EC 1.1.1.22), for the production of UDP-glucuronic acid from UDP-glucose.

Results

In cell extracts no activity was detected. Therefore, cells were permeabilized with 0.3 % (v/v) Triton X-100. After washing away all low molecular weight metabolites, the permeabilized cells were directly used as whole cell biocatalyst. Substrates were 5 mM UDP-glucose and 10 mM NAD+. Divalent cations were not added to the reaction medium as they promoted UDP-glucose hydrolysis. With this reaction system 5 mM UDP-glucose were converted into 5 mM UDP-glucuronic acid within 3 h.

Conclusions

Recombinant permeabilized cells of S. pombe can be used to synthesize UDP-glucuronic acid with 100 % yield and selectivity.
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Hierarchical shotgun sequencing remains the method of choice for assembling high‐quality reference sequences of complex plant genomes. The efficient exploitation of current high‐throughput technologies and powerful computational facilities for large‐insert clone sequencing necessitates the sequencing and assembly of a large number of clones in parallel. We developed a multiplexed pipeline for shotgun sequencing and assembling individual bacterial artificial chromosomes (BACs) using the Illumina sequencing platform. We illustrate our approach by sequencing 668 barley BACs (Hordeum vulgare L.) in a single Illumina HiSeq 2000 lane. Using a newly designed parallelized computational pipeline, we obtained sequence assemblies of individual BACs that consist, on average, of eight sequence scaffolds and represent >98% of the genomic inserts. Our BAC assemblies are clearly superior to a whole‐genome shotgun assembly regarding contiguity, completeness and the representation of the gene space. Our methods may be employed to rapidly obtain high‐quality assemblies of a large number of clones to assemble map‐based reference sequences of plant and animal species with complex genomes by sequencing along a minimum tiling path.  相似文献   
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The trans‐Golgi network (TGN) is the main secretory pathway sorting station, where cargoes are packed into appropriate transport vesicles targeted to specific destinations. Exomer is a cargo adaptor necessary for direct transport of a subset of cargoes from the TGN to the plasma membrane in yeast. Here, we show that unlike classical adaptor complexes, exomer is not recruited en bloc to the TGN, but rather assembles through a stepwise pathway, in which first the scaffold protein Chs5 and then the cargo‐binding units, the ChAPs, are recruited. Although all ChAPs are able to assemble functional exomer complexes, they do so with different efficiencies. The mutual relationship between ChAPs varies from cooperation to competition depending on their expression levels and affinities to Chs5 allowing an optimized and efficient cargo transport. The multifactorial assembly pathway results in an exquisitely fine‐tuned adaptor complex, enabling the cell to quickly respond and adapt to changes such as stress.  相似文献   
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Internalization of gap junction plaques results in the formation of annular gap junction vesicles. The factors that regulate the coordinated internalization of the gap junction plaques to form annular gap junction vesicles, and the subsequent events involved in annular gap junction processing have only relatively recently been investigated in detail. However it is becoming clear that while annular gap junction vesicles have been demonstrated to be degraded by autophagosomal and endo-lysosomal pathways, they undergo a number of additional processing events. Here, we characterize the morphology of the annular gap junction vesicle and review the current knowledge of the processes involved in their formation, fission, fusion, and degradation. In addition, we address the possibility for connexin protein recycling back to the plasma membrane to contribute to gap junction formation and intercellular communication. Information on gap junction plaque removal from the plasma membrane and the subsequent processing of annular gap junction vesicles is critical to our understanding of cell-cell communication as it relates to events regulating development, cell homeostasis, unstable proliferation of cancer cells, wound healing, changes in the ischemic heart, and many other physiological and pathological cellular phenomena.  相似文献   
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