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71.
Christina Liedert Jörg Bernhardt Dirk Albrecht Birgit Voigt Michael Hecker Mirja Salkinoja‐Salonen Peter Neubauer 《Proteomics》2010,10(3):555-563
2‐DE reference maps for Deinococcus geothermalis cytosolic and cell envelope proteomes were constructed. In total, 403 spots were identified as 299 different proteins. Unique in the proteomes were four subunits of V‐type ATPase and Deinococcus specific proteins constituting one‐fourth of cell envelope proteome. The cytoplasmic proteome included enzymes of the central carbon metabolism, chaperones, enzymes of protein and DNA repair, and oxidative stress. A total of 34 abundant proteins with unknown function may relate to the extreme stress tolerance of D. geothermalis. 相似文献
72.
J. M. Maia C. E. Costa de Macedo E. L. Voigt J. B. S. Freitas J. A. G. Silveira 《Biologia Plantarum》2010,54(1):159-163
The aim of this work was to investigate the role of the antioxidant enzymes in salt tolerance comparing the salt-sensitive
(Pérola) and a salt-tolerant (Pitiúba) cultivar of cowpea [Vigna unguiculata (L.) Walp.]. Salt stress (100 mM NaCl for 8 d) reduced the leaf growth rate more in the sensitive cultivar. The salt-induced
decrease in the relative water content, Na+ accumulation and increase in leaf electrolyte leakage was similar in both cultivars. Salt stress induced a higher increase
in the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX) and phenol peroxidase (POX) in the tolerant cultivar
than in sensitive one. 相似文献
73.
Bauera E Williams BA Voigt C Mosenthin R Verstegen MW 《Archives of animal nutrition》2010,64(5):394-411
Increased carbohydrate fermentation, compared with protein fermentation, could benefit gut health. In two in vitro experiments, the effect of carbohydrate-rich feed ingredients on fermentation characteristics of ileal chyme from pigs was assessed, using the cumulative gas production technique. Ingredients of the first experiment included gums, inulins, pectins, transgalacto-oligosaccharides, lactose and xylan. In the second experiment, a gum, pectin and transgalacto-oligosaccharides were added at different starting weights, to determine their effects on fermentation characteristics of chyme, in relation to differences in the carbohydrate concentrations. In comparison to fermentation of chyme alone, added carbohydrates led to higher total gas production (p < 0.05), faster maximum rate of gas production (except for xylan) (p < 0.05), and a decreased branched-chain fatty acids to straight chain fatty acids ratio (BCR) (p < 0.05). In the second experiment, for all carbohydrate ingredients, the BCR decreased with increasing starting weights (p < 0.05). If these supplemented dietary carbohydrates were to reach the terminal ileum of the living animal, carbohydrate fermentation in the large intestine could be stimulated, which is known to have beneficial effects on host health. 相似文献
74.
Dietrich CG Martin IV Porn AC Voigt S Gartung C Trautwein C Geier A 《American journal of physiology. Gastrointestinal and liver physiology》2007,293(3):G585-G590
Fasting induces numerous adaptive changes in metabolism by several central signaling pathways, the most important represented by the HNF4alpha/PGC-1alpha-pathway. Because HNF4alpha has been identified as central regulator of basolateral bile acid transporters and a previous study reports increased basolateral bile acid uptake into the liver during fasting, we hypothesized that HNF4alpha is involved in fasting-induced bile acid uptake via upregulation of basolateral bile acid transporters. In rats, mRNA of Ntcp, Oatp1, and Oatp2 were significantly increased after 48 h of fasting. Protein expression as determined by Western blot showed significant increases for all three transporters 72 h after the onset of fasting. Whereas binding activity of HNF1alpha in electrophoretic mobility shift assays remained unchanged, HNF4alpha binding activity to the Ntcp promoter was increased significantly. In line with this result, we found significantly increased mRNA expression of HNF4alpha and PGC-1alpha. Functional studies in HepG2 cells revealed an increased endogenous NTCP mRNA expression upon cotransfection with either HNF4alpha, PGC-1alpha, or a combination of both. We conclude that upregulation of the basolateral bile acid transporters Ntcp, Oatp1, and Oatp2 in fasted rats is mediated via the HNF4alpha/PGC-1alpha pathway. 相似文献
75.
Erpenbeck D Nichols SA Voigt O Dohrmann M Degnan BM Hooper JN Wörheide G 《Journal of molecular evolution》2007,64(5):543-557
Many rDNA molecular phylogenetic studies result in trees that are incongruent to either alternative gene tree reconstructions
and/or morphological assumptions. One reason for this outcome might be the application of suboptimal phylogenetic substitution
models. While the most commonly implemented models describe the evolution of independently evolving characters fairly well,
they do not account for character dependencies such as rRNA strands that form a helix in the ribosome. Such nonindependent
sites require the use of models that take into account the coevolution of the complete nucleotide pair (doublet). We analyzed
28S rDNA (LSU) demosponge phylogenies using a “doublet” model for pairing sites (rRNA-helices) and compared our findings with
the results of “standard” approaches using Bayes factors. We demonstrate that paired and unpaired sites of the same gene result
in different reconstructions and that usage of a doublet model leads to more reliable demosponge trees. We show the influence
of more sophisticated models on phylogenetic reconstructions of early-branching metazoans and the phylogenetic relationships
of demosponge orders.
[Reviewing Editor: Dr. Rasmus Nielsen] 相似文献
76.
Kirchengast S Mayer M Voigt M 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2007,65(4):415-426
Human reproduction is a biological phenomenon, however, sociocultural factors such as marital status influence pregnancy outcome and reproductive success. In the present study the impact of maternal marital status on pregnancy outcome was tested for all births, which had taken place in Austria between 1999 and 2004, which met the following criteria: single births, nulliparity, mothers older than 19 years (n = 179 830). The rate of preterm delivery (< 37 beginning weeks of gestation) and rate of low birth weight (< 2500 g) among term births were significantly higher among unmarried mothers in comparison to married mothers. Additionally the newborns of unmarried mothers were significantly lighter and shorter than those of married mothers. This was especially true of immigrant mothers. No significant differences between married and unmarried mothers were found regarding mode of delivery. Even at the beginning of the 21st century unmarried status represents an important stress factor for pregnant women. 相似文献
77.
Series of novel N-acyloxy-1,4-dihydropyridines have been synthesized and evaluated as P-glycoprotein inhibitors in an in vitro assay to estimate their potential to act as multidrug resistance modulators in cancer cells. Structure-activity relationships are discussed and prove a significant and regiospecific influence of certain functional groups. 相似文献
78.
Comparative analysis of the complete genome sequence of the plant growth-promoting bacterium Bacillus amyloliquefaciens FZB42 总被引:11,自引:0,他引:11
Chen XH Koumoutsi A Scholz R Eisenreich A Schneider K Heinemeyer I Morgenstern B Voss B Hess WR Reva O Junge H Voigt B Jungblut PR Vater J Süssmuth R Liesegang H Strittmatter A Gottschalk G Borriss R 《Nature biotechnology》2007,25(9):1007-1014
Bacillus amyloliquefaciens FZB42 is a Gram-positive, plant-associated bacterium, which stimulates plant growth and produces secondary metabolites that suppress soil-borne plant pathogens. Its 3,918-kb genome, containing an estimated 3,693 protein-coding sequences, lacks extended phage insertions, which occur ubiquitously in the closely related Bacillus subtilis 168 genome. The B. amyloliquefaciens FZB42 genome reveals an unexpected potential to produce secondary metabolites, including the polyketides bacillaene and difficidin. More than 8.5% of the genome is devoted to synthesizing antibiotics and siderophores by pathways not involving ribosomes. Besides five gene clusters, known from B. subtilis to mediate nonribosomal synthesis of secondary metabolites, we identified four giant gene clusters absent in B. subtilis 168. The pks2 gene cluster encodes the components to synthesize the macrolactin core skeleton. 相似文献
79.
D. Pedreschi S. Mariani J. Coughlan C. C. Voigt M. O'Grady J. Caffrey M. Kelly‐Quinn 《Journal of fish biology》2015,87(4):876-894
The first comprehensive investigation of pike Esox lucius trophic ecology in a region (Ireland) where they have long been thought to be a non‐native species is presented. Diet was investigated across habitat types (lake, river and canal) through the combined methods of stable‐isotope and stomach content analyses. Variations in niche size, specialization and the timing of the ontogenetic dietary switch were examined, revealing pronounced opportunism and feeding plasticity in E. lucius, along with a high occurrence of invertivory (up to 60 cm fork length, LF) and a concomitant delayed switch to piscivory. Furthermore, E. lucius were found to primarily prey upon the highly available non‐native roach Rutilus rutilus, which may alleviate predation pressure on brown trout Salmo trutta, highlighting the complexity of dynamic systems and the essential role of research in informing effective management. 相似文献