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951.
Daniel O. Cicero Gaetano Barbato Uwe Koch Paolo Ingallinella Elisabetta Bianchi Sonia Sambucini Petra Neddermann Raffaele De Francesco Antonello Pessi Renzo Bazzo 《Journal of biomolecular NMR》2001,20(1):23-29
A new isotope-filtered experiment has been designed to measure homonuclear three-bond J(HNH) coupling constants of unlabeled peptides complexed with labeled proteins. The new experiment is based on the 3D HNHA pulse scheme, and belongs to the `quantitative J-correlation' type. It has been applied to a decapeptide inhibitor bound to the proteinase domain of the NS3 protein of human hepatitis C virus (HCV). 相似文献
952.
953.
Martin Brändle Uwe Amarell Harald Auge Stefan Klotz Roland Brandl 《Biodiversity and Conservation》2001,10(9):1497-1511
We analysed species richness of plants and true bugs (Insecta, Heteroptera) along a pollution gradient in Scots pine stands in Central Germany. As a consequence of particulate deposition, pH-values of soils increased in the vicinity of the emission source. Therefore, emission increased productivity. Species richness of plants increased with decreasing distance from emission source, and thus with increasing productivity. Similarly, species richness of herbivorous Heteroptera increased with decreasing distance from emission source, whereas, surprisingly, abundance decreased. The proportion of specialised herbivorous bug species is largest in the vicinity of the emission source. Thus, the diversity pattern of herbivores may be explained by the specialisation hypothesis and not the consumer rarity hypothesis. Species richness and abundance of carnivorous Heteroptera showed no significant trend along the gradient. Overall our data favour the bottom-up control of species diversity in the analysed system. 相似文献
954.
955.
We have evaluated surface plasmon resonance with avidin-biotin immobilized liposomes tocharacterize membrane binding of ubiquitous mitochondrial creatine kinase (uMtCK). Whilethe sarcomeric sMtCK isoform is well known to bind to negatively charged phospholipids,especially cardiolipin, this report provides the first experimental evidence on the membraneinteraction of an uMtCK isoform. Qualitative measurements showed that liposomes containing16% (w/w) cardiolipin bind octameric as well as dimeric human uMtCK and also cytochromec, but not bovine serum albumin. Quantitative parameters could be derived only for themembrane interaction of octameric human uMtCK using an improved analytical approach.Association and dissociation kinetics of octameric uMtCK fit well to a model for heterogeneousinteraction suggesting two independent binding sites. Rate constants of the two sites differedby one order of magnitude, while their affinity constants were both about 80–100 nM. Thedata obtained demonstrate that surface plasmon resonance with immobilized liposomes is asuitable approach to characterize the binding of peripheral proteins to a lipid bilayer and thatthis method yields consistent quantitative binding parameters. 相似文献
956.
Ralf T. Otto Holger Scheib Uwe T. Bornscheuer Jü rgen Pleiss Christoph Syldatk Rolf D. Schmid 《Journal of Molecular Catalysis .B, Enzymatic》2000,8(4-6):201-211
Arylaliphatic glycolipids are known for their pharmaceutical and medicinal properties. We found that a great variety of arylaliphatic esters can be synthesized from non-activated substrates like glucose or the natural occurring drug salicin using lipase B from Candida antarctica (CAL-B). However, esters based on aromatic carboxylic acids or unsaturated arylaliphatic acids, like cinnamic acid and its derivatives, which are known to display anticancer activity, could not be obtained. In this work, we performed computer-aided molecular modeling based on data of our work published recently and syntheses of new glycolipids to understand why some substances are accepted by CAL-B while some are not. For this purpose, we investigated the accessibility of the lipase binding site for the arylaliphatic acyl donors as well as the steric interactions between the aglycons of glucosides and the residues of the alcohol binding pocket in order to elucidate potentials and limitations of CAL-B for the synthesis of aromatic glycolipids. 相似文献
957.
Summary A metatheoretical and historiographical re-analysis of the Evolutionary Synthesis (the process) and the Synthetic Theory (the
result) leads to the following conclusion: The Synthetic Theory is not a reductionistic, but rather a structuralistic theory
with a limited range of relevant hierarchical levels. Historically the Synthesis was not a sudden event but a rational long-term
project carried out between 1930 and 1950 by a large number of biologists in several countries. In the second part of our
paper the contributions of several German biologists to the Synthesis are analyzed. 相似文献
958.
Schlattner Uwe Forstner Michael Eder Michael Stachowiak Olaf Fritz-Wolf Karin Wallimann Theo 《Molecular and cellular biochemistry》1998,184(1-2):125-140
Mitochondrial creatine kinase (Mi-CK) is a central enzyme in energy metabolism of tissues with high and fluctuating energy requirements. In this review, recent progress in the functional and structural characterization of Mi-CK is summarized with special emphasis on the solved X-ray structure of chicken Mib-CK octamer (Fritz-Wolf et al., Nature 381, 341-345, 1996). The new results are discussed in a historical context and related to the characteristics of CK isoforms as known from a large number of biophysical and biochemical studies. Finally, two hypothetical functional aspects of the Mi-CK structure are proposed: (i) putative membrane binding motifs at the top and bottom faces of the octamer and (ii) a possible functional role of the central 20 Å channel. 相似文献
959.
960.