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211.
In sugar beet production, weed control is one of the most important and most expensive practices to ensure yield. Since glyphosate-resistant sugar beets are not yet approved for cultivation in the EU, little commercial experience exists with these sugar beets in Europe. Experimental field trials were conducted at five environments (Germany, Poland, 2010, 2011) to compare the effects of glyphosate with the effects of conventional weed control programs on the development of weeds, weed control efficiency and yield. The results show that the glyphosate weed control programs compared to the conventional methods decreased not only the number of herbicide applications but equally in magnitude decreased the dosage of active ingredients. The results also showed effective weed control with glyphosate when the weed covering was greater and sugar beets had a later growth stage of four true leaves. Glyphosate-resistant sugar beets applied with the glyphosate herbicide two or three times had an increase in white sugar yield from 4 to 18 % in comparison to the high dosage conventional herbicide systems. In summary, under glyphosate management sugar beets can positively contribute to the increasingly demanding requirements regarding efficient sugar beet cultivation and to the demands by society and politics to reduce the use of chemical plant protection products in the environment.  相似文献   
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The di-tripeptide transport system (DtpT) of Lactococcus lactis was purified to apparent homogeneity by pre-extraction of crude membrane vesicles with octaethylene glycol monodecyl ether (C10E8), followed by solubilization with n-dodecyl-beta-D-maltoside (DDM) and chromatography on a Ni-NTA resin. The DtpT protein was reconstituted into detergent-destabilized preformed liposomes prepared from E. coli phospholipid/ phosphatidylcholine. A variety of detergents were tested for their ability to mediate the membrane reconstitution of DtpT and their effectiveness to yield proteoliposomes with a high transport activity. The highest activities were obtained with TX100, C12E8 and DM, whereas DDM yielded relatively poor activities, in particular when this detergent was used at concentrations beyond the onset of solubilization of the preformed liposomes. Parallel with the low activity, significant losses of lipid were observed when the reconstitution was performed at high DDM concentrations. This explained at least part of the reduced transport activity as the DtpT protein was highly dependent on the final lipid-to-protein ratios in the proteoliposomes. Consistent with the difference in mechanism of DDM- and TX100-mediated membrane protein reconstitution, the orientation of the DtpT protein in the membrane was random with DDM and inside-in when T100 was used. The methodology to determine the orientation of membrane-reconstituted proteins from the accessibility of cysteines for thiol-specific reagents is critically evaluated.  相似文献   
214.
This study explores the influence of a selection of adjuvants and of three different nozzle sizes on the foliar application of entomopathogenic nematodes (EPNs). Two EPN species were studied: Steinernema feltiae and Steinernema carpocapsae. A viability test of EPNs suspended in different solutions of adjuvants showed that all selected alcohol ethoxylates and an alkyl polysaccharide have an immobilising effect on the selected nematode species. In a sedimentation test, xanthan gum proved to be the only adjuvant in a broad selection, capable of delaying sedimentation of EPNs in suspension. Without xanthan gum, sedimentation of S. carpocapsae and S. feltiae was noticeable after 20 and 10 minutes, respectively. When xanthan gum (0.3 g/L) was added to the suspension, no signs of sedimentation were noticed after 20 minutes with both EPN species. An ISO 02 flat fan nozzle can clog when spraying S. carpocapsae. A deposition test determined that an ISO 04 standard flat fan nozzle provides a higher relative deposition on cauliflower leaves and is therefore a better nozzle choice than the bigger ISO 08 standard flat fan nozzle for spraying S. carpocapsae. The addition of a spreading agent improved the deposition of S. carpocapsae. Adding xanthan gum to the EPN-spreading agent mixtures did not further improve deposition.  相似文献   
215.
Genetic kidney diseases represent a significant proportion of kidney diseases manifesting in childhood and adolescence, but are also gaining importance in slowly progressive or late-onset adult diseases. A significant portion of kidney diseases particularly in childhood are associated with end stage renal disease and/or other relevant morbidity. An early (molecular) diagnosis can be a prerequisite for a better prognostic assessment and provides opportunities in terms of optimized symptomatic therapy. Mechanistically speaking, mutations in ion channel-associated nephropathy represent—in addition to structural defects of the glomerular filter (e.g., COL4A3, LAMB2, nephrin) and disorders of signaling pathways that are relevant for the development of the urogenital tract (e.g., HNF1B, WT1)—a significant proportion of the group with respect to number and prototypes. Determination of the molecular genetics of (hypokalemic) salt-losing tubulopathies has contributed significantly to our understanding of the central role of the kidney in salt balance. The spectrum of renal ion channelopathies is shown using the example of classical salt-losing tubulopathies (Bartter syndrome and Gitelman syndrome), the transient receptor potential (TRP) channel group and the role of channel changes in aldosteronism and congenital hypertension.  相似文献   
216.
Transglutaminases (TG) form a family of enzymes that catalyse various post-translational modifications of glutamine residues in proteins and peptides including intra- and intermolecular isopeptide bond formation, esterification and deamidation. We have characterized a novel member of the mammalian TG family, TG6, which is expressed in a human carcinoma cell line with neuronal characteristics and in mouse brain. Besides full-length protein, alternative splicing results in a short variant lacking the second β-barrel domain in man and a variant with truncated β-sandwich domain in mouse. Biochemical data show that TG6 is allosterically regulated by Ca2+ and guanine nucleotides. Molecular modelling indicates that TG6 could have Ca2+ and GDP-binding sites related to those of TG3 and TG2, respectively. Localization of mRNA and protein in the mouse identified abundant expression of TG6 in the central nervous system. Analysis of its temporal and spatial pattern of induction in mouse development indicates an association with neurogenesis. Neuronal expression of TG6 was confirmed by double-labelling of mouse forebrain cells with cell type-specific markers. Induction of differentiation in mouse Neuro 2a cells with NGF or dibutyryl cAMP is associated with an upregulation of TG6 expression. Familial ataxia has recently been linked to mutations in the TGM6 gene. Autoantibodies to TG6 were identified in immune-mediated ataxia in patients with gluten sensitivity. These findings suggest a critical role for TG6 in cortical and cerebellar neurons.  相似文献   
217.
An important criterion for the selection of a probiotic bacterial strain is its ability to adhere to the mucosal surface. Adhesion is usually mediated by proteins or other components located on the outer cell surface of the bacterium. In the present study we characterized the adhesive properties of two classical intracellular enzymes glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and enolase (ENO) isolated from the outer cell surface of the probiotic bacterium Lactobacillus plantarum 299v. None of the genes encoded signal peptides or cell surface anchoring motifs that could explain their extracellular location on the bacterial surface. The presence of the glycolytic enzymes on the outer surface was verified by western blotting using polyclonal antibodies raised against the specific enzymes. GAPDH and ENO showed a highly specific binding to plasminogen and fibronectin whereas GAPDH but not ENO showed weak binding to mucin. Furthermore, a pH dependent and specific binding of GAPDH and ENO to intestinal epithelial Caco-2 cells at pH 5 but not at pH 7 was demonstrated. The results showed that these glycolytic enzymes could play a role in the adhesion of the probiotic bacterium L. plantarum 299v to the gastrointestinal tract of the host. Finally, a number of probiotic as well non-probiotic Lactobacillus strains were analyzed for the presence of GAPDH and ENO on the outer surface, but no correlation between the extracellular location of these enzymes and the probiotic status of the applied strains was demonstrated.  相似文献   
218.
Eremiadinae, one of three subfamilies of Lacertidae, are distributed throughout Asia and Africa. Previous phylogenetic studies suggested that one of the main groups of Eremiadinae (the Ethiopian clade) consist of two clades with predominately East‐African and South‐African distribution. Yet, especially the latter one, which includes the genera Pedioplanis, Meroles, Ichnotropis, Tropidosaura and Australolacerta, was not well supported in the molecular phylogenetic analysis. In this study, we analysed the phylogenetic relationships among the genera of the ‘South African clade’ to assess whether this group actually forms a highly supported clade and to address questions concerning the monophyly of the genera. We sequenced sections of the widely used mitochondrial genes coding for 16S rRNA, 12S rRNA and cytochrome b (altogether 2045 bp) as well as the nuclear genes c‐mos, RAG‐1, PRLR, KIF24, EXPH5 and RAG‐2 (altogether 4473 bp). The combined data set increased the support values for several nodes considerably. Yet, the relationships among five major lineages within the ‘South African clade’ are not clearly resolved even with this large data set. We interpret this as a ‘hard polytomy’ due to fast radiation within the South African lacertids. The combined tree based on nine marker genes provides strong support for the ‘South African Clade’ and its sister group relationship with the ‘East African Clade’. Our results confirm the genus Tropidosaura as a monophylum, while Ichnotropis is paraphyletic in our trees: Ichnotropis squamulosa appears more closely related to Meroles than to Ichnotropis capensis. Furthermore, the monophyly of Meroles is questionable as well. Based on our results, I. squamulosa should be transferred from Ichnotropis into the genus Meroles. Also, the two species of Australolacerta (A. australis and A. rupicola) are very distantly related and the genus is perhaps paraphyletic, too. Finally we propose a phylogeographical scenario in the context of palaeoclimatic data and compare it with a previously postulated hypothesis.  相似文献   
219.
Hyphae of filamentous Ascomycota consist of compartments that are connected via septal pores. To avoid a dramatic loss of cellular content after wounding, fungi developed mechanisms to occlude their septal pores. In most Pezizomycotina, so‐called Woronin bodies are anchored in proximity to the pore. This is a prominent example for precise spatial positioning of organelles, but so far the underlying molecular organization has remained largely unknown. Using the pathogenic mould Aspergillus fumigatus, we provide evidence that Woronin bodies are important for stress resistance and virulence. Furthermore the molecular machinery anchoring them at the septum is described. Namely, we have identified Lah as the tethering protein and provide evidence that the Woronin body protein HexA binds to the septal pore in a Lah‐dependent manner. Moreover, we demonstrate that a striking poly‐histidine motif targets HexA to the septal cell wall. Thus, the axis HexA‐Lah is an excellent candidate for the tether linking Woronin bodies to the septum. This model applies to A. fumigatus, but most likely also to the vast majority of the Pezizomycotina. Our findings shed light on the evolution of Woronin body anchoring and provide a basis for the development of novel strategies to combat fungal pathogens like A. fumigatus.  相似文献   
220.
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