排序方式: 共有14条查询结果,搜索用时 0 毫秒
1.
2.
3.
Sergio Mauro Françoise Van Eycken Najib Challou Patrick Lucas Michèle L'Oiseau 《Physiologia plantarum》2005,124(3):323-335
The response of superoxide dismutases (SOD, EC1.15.1.1) to chilling-induced oxidative stress in differentially sensitive maize genotypes ( Zea mays L) was examined. A native 2D-PAGE system that resolves the maize leaf SOD isoforms has been developed. The chloroplastic SOD activity was resolved into four Cu/Zn SOD isoforms designated SOD1a→d with pI values of 3.9, 4.0, 4.5 and 5.6, respectively. These SODs are located in the stroma and display a higher resistance to hydrogen peroxide inactivation than the cytosol Cu/ZnSODs. They operate as 32 kDa homodimers and have an AT motif at the NH2 -terminal, which characterizes the chloroplastic SODs of most species. A light chilling treatment resulted in a rapid increase in the activity of SOD1a and SOD1b . Because this increase was observed in the presence of the protein synthesis inhibitor cycloheximide, it is suggested that short-term regulation of chloroplastic SODs occurs at a post-translational level. 相似文献
4.
Isabelle E.J.A. François Bruno P.A. Cammue Sara Bresseleers Hein Fleuren Georges Hoornaert Vaibhav P. Mehta Sachin G. Modha Erik V. Van der Eycken Karin Thevissen 《Bioorganic & medicinal chemistry letters》2009,19(15):4064-4066
We synthesized a family of 3,5-dichloropyrazin-2(1H)-one derivatives and assessed their in vitro fungicidal activity against Candida albicans. Compounds 11 and 20 were most active against C. albicans and induced accumulation of reactive oxygen species in this pathogen. Using a genome-wide approach in the yeast Saccharomyces cerevisiae, we demonstrated that genes involved in vacuolar functionality and DNA-related functions play an important role in cellular mechanisms underlying the fungicidal activity of these compounds. 相似文献
5.
An improved chemical approach toward the C-terminal sequence analysis of proteins containing all natural amino acids. 总被引:1,自引:1,他引:0 下载免费PDF全文
K. Hardeman B. Samyn J. Van der Eycken J. Van Beeumen 《Protein science : a publication of the Protein Society》1998,7(7):1593-1602
An improved chemical method, capable of derivatizing all natural amino acids to their corresponding thiohydantoins, is described. This involves activation by acetyl chloride in TFA followed by derivatization with ammonium thiocyanate. Possible interference of reactive side chains was investigated by reacting N-acetylamino acids as well as several peptides with propionyl chloride instead of acetyl chloride. The products were characterized by PDMS mass spectrometry and 1H-NMR. This chemical method allows, for the first time, complete derivatization of N-acetylproline to proline thiohydantoin. Applying this chemistry to peptides with a C-terminal proline, the yields for formation of proline thiohydantoin were found to be up to 60%, depending on the peptide sequence. The previous inability to derivatize C-terminal proline to thiohydantoin was thought to stem from the fact that proline cannot form the oxazolonium ion required for efficient reaction with the thiocyanate ion. However, we have found mass spectrometric evidence for the existence of a proline oxazolonium ion, under basic as well as under acidic conditions. This improvement in derivatization of C-terminal amino acids including proline is a major step forward in the development of a general chemical C-terminal sequencing method that permits the C-terminal sequence analysis of proteins of any amino acid composition. 相似文献
6.
Claudia Cavalluzzo Frauke Christ Arnout Voet Ajendra Sharma Brajendra Kumar Singh Kam Y.J. Zhang Eveline Lescrinier Marc De Maeyer Zeger Debyser Erik Van der Eycken 《Journal of peptide science》2013,19(10):651-658
The integration of the viral DNA into the host genome is one of the essential steps in the HIV replication cycle. This process is mediated by the viral enzyme integrase (IN) and lens epithelium‐derived growth factor (LEDGF/p75). LEDGF/p75 has been identified as a crucial cellular co‐factor of integration that acts by tethering IN to the cellular chromatin. Recently, circular peptides were identified that bind to the C‐terminal domain of IN and disrupt the interaction with LEDGF/p75. Starting from the circular peptides, we identified a short peptidic sequence able to inhibit the LEDGF/p75‐IN interaction at low μM concentration through its binding to the IN binding site of LEDGF/p75. This discovery can lead to the synthesis of peptidomimetics with high anti‐HIV activity targeting the cellular co‐factor LEDGF/p75 and not the viral protein IN. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
7.
Devreux V Wiesner J Jomaa H Van der Eycken J Van Calenbergh S 《Bioorganic & medicinal chemistry letters》2007,17(17):4920-4923
Fosmidomycin, which acts through inhibition of 1-deoxy-D-xylulose phosphate reductoisomerase (DXR) in the non-mevalonate pathway, represents a valuable recent addition to the armamentarium against uncomplicated malaria. In this paper, we describe the synthesis and biological evaluation of E- and Z-alpha,beta-unsaturated alpha-aryl-substituted analogues of FR900098, a fosmidomycin congener, utilizing a Stille or a Suzuki coupling to introduce the aryl group. In contrast with our expectations based on the promising activity earlier observed for several alpha-substituted fosmidomycin analogues, all synthesized analogues exhibited much lower binding affinity for DXR than fosmidomycin. 相似文献
8.
A chromone analog inhibits TNF-alpha induced expression of cell adhesion molecules on human endothelial cells via blocking NF-kappaB activation 总被引:3,自引:0,他引:3
9.
Phenolic profiling of caffeic acid O-methyltransferase-deficient poplar reveals novel benzodioxane oligolignols 下载免费PDF全文
Morreel K Ralph J Lu F Goeminne G Busson R Herdewijn P Goeman JL Van der Eycken J Boerjan W Messens E 《Plant physiology》2004,136(4):4023-4036
Caffeic acid O-methyltransferase (COMT) catalyzes preferentially the methylation of 5-hydroxyconiferaldehyde to sinapaldehyde in monolignol biosynthesis. Here, we have compared HPLC profiles of the methanol-soluble phenolics fraction of xylem tissue from COMT-deficient and control poplars (Populus spp.), using statistical analysis of the peak heights. COMT down-regulation results in significant concentration differences for 25 of the 91 analyzed peaks. Eight peaks were exclusively detected in COMT-deficient poplar, of which four could be purified for further identification using mass spectrometry/mass spectrometry, nuclear magnetic resonance, and spiking of synthesized reference compounds. These new compounds were derived from 5-hydroxyconiferyl alcohol or 5-hydroxyconiferaldehyde and were characterized by benzodioxane moieties, a structural type that is also increased in the lignins of COMT-deficient plants. One of these four benzodioxanes amounted to the most abundant oligolignol in the HPLC profile. Furthermore, all of the differentially accumulating oligolignols involving sinapyl units were either reduced in abundance or undetectable. The concentration levels of all identified oligolignols were in agreement with the relative supply of monolignols and with their chemical coupling propensities, which supports the random coupling hypothesis. Chiral HPLC analysis of the most abundant benzodioxane dimer revealed the presence of both enantiomers in equal amounts, indicating that they were formed by radical coupling reactions under simple chemical control rather than guided by dirigent proteins. 相似文献
10.
A molecular study of root-knot nematode-induced feeding sites 总被引:6,自引:0,他引:6
Walter Van der Eycken Janice de Almeida Engler Dirk Inzé Marc Van Montagu Godelieve Gheysen 《The Plant journal : for cell and molecular biology》1996,9(1):45-54
In a compatible interaction, root-knot nematodes ( Meloidogyne ) induce a sophisticated feeding site shortly after they have penetrated the plant root. The feeding site contains metabolically highly active giant cells. To gain insight into the molecular aspects that are typical for giant cells, a cDNA library from tomato roots infected with Meloidogyne incognita was differentially screened to find induced genes. Among the genes identified, two extensin genes ( Lemmi8 and Lemmi11 ) and a Lea -like gene ( Lemmi9 ) were studied further. 相似文献