5 Lipoxygenase
Mostrando 37-48 de 242 artigos, teses e dissertações.
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37. Membrane-Associated and Soluble Lipoxygenase Isoforms in Tomato Pericarp (Characterization and Involvement in Membrane Alterations).
Membrane-associated and soluble lipoxygenases from green tomato (Lycopersicon esculentum Mill. cv Ailsa Craig) fruit have been identified. Microsomal lipoxygenase was localized partly in the plasma membrane and tonoplast fractions. The possibilities of glycosyl-phosphatidylinositol or transmembrane polypeptide anchors in the membrane were ruled out by differ
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38. Characterization of leukotriene A4 synthase from murine mast cells: evidence for its identity to arachidonate 5-lipoxygenase.
Leukotriene A4 synthase was purified from the cytosolic fraction of murine mast cells. The enzyme converted 5-hydroperoxy-6-trans-8,11,14-cis-icosatetraenoic acid (5-HPETE) to leukotriene A4. This unstable product was identified by demonstration of two epimers of 6-transleukotriene B4, methanol trapping, as well as further transformation to leukotriene B4 by
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39. Intrinsic 5-lipoxygenase activity is required for neutrophil responsivity.
We found that intrinsic neutrophil 5-lipoxygenase activity was necessary for human neutrophil adherence and chemotaxis in vitro and human neutrophil-mediated acute edematous injury in isolated perfused rat lungs given interleukin 8 intratracheally. Treatment with either Zileuton (a specific reversible competitive inhibitor of 5-lipoxygenase) or MK886 (a spec
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40. Characterization of the human 5-lipoxygenase gene promoter.
Nucleotide sequences that direct transcription of the human 5-lipoxygenase gene have been examined by ligation to the chloramphenicol acetyltransferase gene and determination of chloramphenicol acetyltransferase activity in transfected HeLa and HL-60 cells. Various lengths of 5'-flanking sequences up to 5.9 kilobase pairs 5' of the transcriptional initiation
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41. Effect of the 5-lipoxygenase inhibitor ZD2138 on allergen-induced early and late asthmatic responses.
BACKGROUND--Leukotrienes are lipid mediators generated from arachidonic acid by the 5-lipoxygenase pathway which may play an important part in the pathophysiology of asthma. Previous studies have demonstrated attenuation of the allergen-induced early and late asthmatic responses by leukotriene receptor antagonists. The effect of the 5-lipoxygenase inhibitor
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42. Arachidonate metabolism via lipoxygenase and 12L-hydroperoxy-5,8,10,14-icosatetraenoic acid peroxidase sensitive to anti-inflammatory drugs.
The enzymes of arachidonate metabolism via the lipoxygenase pathway in human platelet cytosol have been characterized and partially purified. The lipoxygenase activity has a pH optimum of 7.3 and reaches half-maximal activity at an arachidonate concentration of 80 microM. The oxidation of arachidonate by these enzymes is inhibited by reagents that modify sul
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43. 5-Lipoxygenase Reaction Products Modulate Alveolar Macrophage Phagocytosis of Klebsiella pneumoniae
The leukotrienes are potent lipid mediators of inflammation formed by the 5-lipoxygenase-catalyzed oxidation of arachidonic acid. Although the effects of leukotrienes on neutrophil chemotaxis and activation have been established, their role in modulating innate host defense mechanisms is poorly understood. In a previous study (M. Bailie, T. Standiford, L. La
American Society for Microbiology.
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44. Native and mutant 5-lipoxygenase expression in a baculovirus/insect cell system.
Human 5-lipoxygenase (EC 1.13.11.34), the key enzyme involved in the transformation of arachidonic acid to the potent biologically active leukotrienes, has been overexpressed in insect cells using a baculovirus expression system. A recombinant baculovirus (3B6) carrying the human 5-lipoxygenase coding sequence downstream of the strong polyhedrin protein prom
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45. Molecular cloning and amino acid sequence of human 5-lipoxygenase.
5-Lipoxygenase (EC 1.13.11.34), a Ca2+-and ATP-requiring enzyme, catalyzes the first two steps in the biosynthesis of the peptidoleukotrienes and the chemotactic factor leukotriene B4. A cDNA clone corresponding to 5-lipoxygenase was isolated from a human lung lambda gt11 expression library by immunoscreening with a polyclonal antibody. Additional clones fro
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46. Cloning of the cDNA for human 12-lipoxygenase.
A full-length cDNA clone encoding 12-lipoxygenase (arachidonate:oxygen 12-oxidoreductase, EC 1.13.11.31) was isolated from a human platelet cDNA library by using a cDNA for human reticulocyte 15-lipoxygenase as probe for the initial screening. The cDNA had an open reading frame encoding 662 amino acid residues with a calculated molecular weight of 75,590. Th
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47. Characterization of the human 5-lipoxygenase gene.
The gene for human 5-lipoxygenase has been isolated from three different bacteriophage genomic libraries and a genomic cosmid library. The gene spans greater than 82 kilobases and consists of 14 exons. The size range for the exons is 82-613 base pairs, whereas that for the introns is approximately 200 bp to greater than 26 kb. A major site of transcription i
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48. Integrin-dependent homotypic adhesion of neutrophils. Arachidonic acid activates Raf-1/Mek/Erk via a 5-lipoxygenase- dependent pathway.
AA stimulates integrin-dependent neutrophil adhesion, a critical early step in acute inflammation. However, neither the signaling pathway(s) of AA-stimulated adhesion, nor whether AA acts directly or through the generation of active metabolites, has been elucidated. Previously, we have observed a tight association between neutrophil Erk activation and homoty