Search results for "CLEAVAGE"
showing 10 items of 281 documents
Lipoprotein-induced phenoloxidase-activity in tarantula hemocyanin.
2015
Phenoloxidases play vital roles in invertebrate innate immune reactions, wound closure and sclerotization processes in arthropods. In chelicerates, where phenoloxidases are lacking, phenoloxidase-activity can be induced in the oxygen carrier hemocyanin in vitro by proteolytic cleavage, incubation with the artificial inducer SDS, or lipids. The role of protein-protein interaction has up to now received little attention. This is remarkable, as lipoproteins - complexes of proteins and lipids - are present at high concentrations in arthropod hemolymph. We characterized the three lipoproteins present in tarantula hemolymph, two high-density lipoproteins and one very high-density lipoprotein, and…
Photochemical Synthesis and Reactivity of New Chloro-Bridged Complexes with Tungstenocene (η5-C5H5)(η5-C5H4PPh2)WClX (X = H, Cl) and Tetracarbonylmet…
1999
Chloro-bridged bimetallic complexes (η5-C5H5)[η5-C5H4PPh2M′(CO)4]W(μ-Cl)X [X = Cl (3), × = H (4); M′ = Cr, W] were prepared by photochemical irradiation of (η5-C5H5)[η5-C5H4PPh2M′(CO)5]WClX [X = Cl (1), × = H (2); M′ = Cr, W]. The reactivity of the chloro-bridged complexes towards Lewis bases was studied; by exposure to CO or phosphanes, a facile cleavage of the chloro bridge accompanied by regio- and stereospecific coordination at M′ occurs. The X-ray structure of complex 3 (M′ = W) is reported.
The Reductive σ Bond Cleavage of Barbaralane and 2,6‐Diphenylbarbaralane
1987
Barbaralane (2) and 2,6-diphenylbarbaralane (8) are synthesized in a straightforward way. The reductive cleavage of the strained hydrocarbons is achieved with alkali metals. The structure of the metallation products, in particular the bonding in the resulting allyl moieties, is elucidated by 1H- and 13C-NMR spectroscopy. The chemical behavior (oxidation, protonation, alkylation) sheds light on the modes of stabilization of the alkali metal derivatives. Die reduktive σ-Bindungsspaltung von Barbaralan und 2,6-Diphenylbarbaralan Barbaralan (2) und 2,6-Diphenylbarbaralan (8) werden auf rationelle Weise synthetisiert und die gespannten Kohlenwasserstoffe durch Reaktion mit Alkalimetallen redukti…
Die unsymmetrischen Cyclooctadienine: 1,3‐Cyclooctadien‐5‐in und 1,6‐Cyclooctadien‐3‐in
1985
Verschiedene Varianten des synthetischen Zugangs zu den beiden Titelverbindungen 15 und 45 werden diskutiert. 15 und 45 konnen in situ umgesetzt werden. Fur die Isolierung in reiner Form ist ihre mittlere Lebensdauer zu gering. Sie isomerisieren sich auf der C8H8-Energiehyperflache zu Styrol (47) und/oder Benzocyclobuten (22).
Synthesis and X-ray Crystallographic Characterization of (μ-(Diphenylphosphino)phenyl-C2,P)palladium Bromide. A Novel Tetranuclear Metalated Compound
1997
The synthesis and crystal structure of a tetranuclear palladium cluster, [Pd(PC)Br]4 (PC) = [P(C6H4)Ph2]-), is described. Cleavage of this cluster with phosphines yields the mononuclear species Pd(PC)Br(P) in the form of cis and trans isomers. An equilibrium between mono- and tetranuclear species is observed for P = PCBr.
Monocyte Interleukin-1 Secretion Is Regulated by the Sequential Action of γ-Interferon and Interleukin-2 Involving Monocyte Surface Expression of Int…
1989
Interleukin-1 (IL-1) is a polypeptide synthesized as a high-mol.-wt. precursor and subsequently secreted after proteolytic cleavage to 17500-dalton active forms in murine [1] and human cells [2]. Recently, cDNAs for murine [3] and for two distinct human IL-1 species, IL-1α and IL- 1β, have been isolated, sequenced, and cloned [2, 4].
Political Cleavages In The Weimar Republic and the Rise of National Socialism
2013
The article deals with the question if the cleavage concept of Lipset and Rokkan can be applied to the rise of National Socialism at the polls and as a mass-integration party. Voter fluctuations within and between political camps are analysed by means of ecological regression analysis as well as the social composition of the NSDAP electorate. Furthermore the social fabric of NSDAP party members between 1925 and 1933 is decribed in terms of the cleavage concept.
Potassium regulates IL-1 beta processing via calcium-independent phospholipase A2.
2000
Abstract We report that potassium leakage from cells leads to activation of the Ca2+-independent phospholipase A2 (iPLA2), and the latter plays a pivotal role in regulating the cleavage of pro-IL-1β by the IL-converting enzyme caspase-1 in human monocytes. K+ efflux led to increases of cellular levels of glycerophosphocholine, an unambiguous indicator of phospholipase A2 activation. Both maturation of IL-1β and formation of glycerophosphocholine were blocked by bromoenol lactone, the specific iPLA2 inhibitor. Bromoenol lactone-dependent inhibition of IL-1β processing was not due to perturbation of the export machinery for pro-IL-1β and IL-1β or to caspase-1 suppression. Conspicuously, activ…
Time-scale of deformation and intertectonic phases revealed by P-T-D-t relationships in the orogenic middle crust of the Orlica-Śnieżnik Dome, Polish…
2014
A section of the orogenic middle crust (Orlica-nienik Dome, Polish/Czech Central Sudetes) was examined to constrain the duration and significance of deformation (D) and intertectonic (I) phases. In the studied metasedimentary synform, three deformation events produced an initial subhorizontal foliation S1 (D-1), a subsequent subvertical foliation S2 (D-2) and a late subhorizontal axial planar cleavage S3 (D-3). The synform was intruded by pre-, syn- and post-D-2 granitoid sheets. Crystallization-deformation relationships in mica schist samples document I1-2 garnet-staurolite growth, syn-D-2 staurolite breakdown to garnet-biotite-sillimanite/andalusite, I2-3 cordierite blastesis and late-D-3…
Proteomic Analyses Reveal an Acidic Prime Side Specificity for the Astacin Metalloprotease Family Reflected by Physiological Substrates
2011
Astacins are secreted and membrane-bound metalloproteases with clear associations to many important pathological and physiological processes. Yet with only a few substrates described their biological roles are enigmatic. Moreover, the lack of knowledge of astacin cleavage site specificities hampers assay and drug development. Using PICS (proteomic identification of protease cleavage site specificity) and TAILS (terminal amine isotopic labeling of substrates) degradomics approaches >3000 cleavage sites were proteomically identified for five different astacins. Such broad coverage enables family-wide determination of specificities N- and C-terminal to the scissile peptide bond. Remarkably, me…