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981.
982.
983.
Veronika Tillander Elisabet Arvidsson Nordström Jenny Reilly Malgorzata Strozyk Paul P. Van Veldhoven Mary C. Hunt Stefan E. H. Alexson 《Cellular and molecular life sciences : CMLS》2014,71(5):933-948
Acyl-CoA thioesterase (ACOT) activities are found in prokaryotes and in several compartments of eukaryotes where they hydrolyze a wide range of acyl-CoA substrates and thereby regulate intracellular acyl-CoA/CoA/fatty acid levels. ACOT9 is a mitochondrial ACOT with homologous genes found from bacteria to humans and in this study we have carried out an in-depth kinetic characterization of ACOT9 to determine its possible physiological function. ACOT9 showed unusual kinetic properties with activity peaks for short-, medium-, and saturated long-chain acyl-CoAs with highest V max with propionyl-CoA and (iso) butyryl-CoA while K cat/K m was highest with saturated long-chain acyl-CoAs. Further characterization of the short-chain acyl-CoA activity revealed that ACOT9 also hydrolyzes a number of short-chain acyl-CoAs and short-chain methyl-branched CoA esters that suggest a role for ACOT9 in regulation also of amino acid metabolism. In spite of markedly different K ms, ACOT9 can hydrolyze both short- and long-chain acyl-CoAs simultaneously, indicating that ACOT9 may provide a novel regulatory link between fatty acid and amino acid metabolism in mitochondria. Based on similar acyl-CoA chain-length specificities of recombinant ACOT9 and ACOT activity in mouse brown adipose tissue and kidney mitochondria, we conclude that ACOT9 is the major mitochondrial ACOT hydrolyzing saturated C2-C20-CoA in these tissues. Finally, ACOT9 activity is strongly regulated by NADH and CoA, suggesting that mitochondrial metabolic state regulates the function of ACOT9. 相似文献
984.
Complexity science has proliferated across academic domains in recent years. A question arises as to whether any useful sense of ‘generalized complexity’ can be abstracted from the various versions of complexity to be found in the literature, and whether it could prove fruitful in a scientific sense. Most attempts at defining complexity center around two kinds of notions: Structural, and temporal or dynamic. Neither of these is able to provide a foundation for the intuitive or generalized notion when taken separately; structure is often a derivative notion, dependent on prior notions of complexity, and dynamic notions such as entropy are often indefinable. The philosophical notion of process may throw light on the tensions and contradictions within complexity. Robustness, for instance, a key quality of complexity, is quite naturally understood within a process-theoretical framework. Understanding complexity as process also helps one align complexity science with holistically oriented predecessors such as General System Theory, while allowing for the reductionist perspective of complexity. These results, however, have the further implication that it may be futile to search for general laws of complexity, or to hope that investigations of complex objects in one domain may throw light on complexity in unrelated domains. 相似文献
985.
Wilfried Schröder 《Archive for History of Exact Sciences》1985,32(1):77-93
Ohne Zusammenfassung
Vorgelegt von
S. Flügge
Herrn Prof. Dr. Dr. h. c. mult. Friedrich Hund
Zur Vollendung seines 88. Geburtstages in Dankbarkeit zugeeignet 相似文献
986.
987.
Tj. B. van Wimersma Greidanus R. M. Buys H. J. G. Hollemans W. de Jong 《Cellular and molecular life sciences : CMLS》1974,30(10):1217-1218
Zusammenfassung Die Empfindlichkeit und Zuverlässigkeit eines neu entwickelten Radioimmunotests für Vasopressin wurde durch Messungen des Vasopressinspiegels im Hypophysenhinterlappen von homozygoten und heterozygoten Ratten für angeborenen Diabetes insipidus geprüft und eine gute Korrelation zwischen dem biologisch und radioimmunologisch gemessenen Vasopressingehalt der Hypophyse nachgewiesen. 相似文献
988.
The bulk of Duhem’s writing which bears on the understanding of mixtures suggests he adopted an Aristotelian position which he opposed only to the atomic view. A third view from antiquity—that of the Stoics—seems not to be taken into account. But his lines of thought are not always as explicit as could be wished. The Stoic view is considered here from a perspective which Duhem might well have adopted. This provides a background against which his somewhat unorthodox Aristotelianism might be understood. 相似文献
989.
990.