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See detailPurification and characterization of glutathione S-transferases from two syrphid flies (Syrphus ribesii and Myathropa florae).
Vanhaelen, Nicolas; Francis, Frédéric ULg; Haubruge, Eric ULg

in Comparative Biochemistry & Physiology Part B (2004), 137(1), 95-100

Glutathione S-transferases (GST) play an important role in the detoxification of many substances including organic pollutants and plant secondary metabolites. We compared the GST of two syrphid species ... [more ▼]

Glutathione S-transferases (GST) play an important role in the detoxification of many substances including organic pollutants and plant secondary metabolites. We compared the GST of two syrphid species, the aphidophagous Syrphus ribesii and the saprophagous Myathropa florea to assess the relation between feeding type and GST patterns. Differences between the GST of the hoverfly species were observed after purification by affinity chromatography, SDS-PAGE and kinetic studies. While the specific activities of the purified enzymes were different, the purification yields were similar. The variation in specific activities was related to the presence of different isoenzymes in both syrphid species by SDS-PAGE. While two bands of 24 and 32 kDa were observed for M. florea, one more band of 26 kDa was present in S. ribesii. When a range of substrate and glutathione concentrations was tested, differences in Km and Vmax between the glutathione S-transferases from both hoverfly species were also observed. These results are discussed in terms of adaptations to the feeding habit and the habitat of the two syrphid species. [less ▲]

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See detailPurification and Characterization of Pbp4a, a New Low-Molecular-Weight Penicillin-Binding Protein from Bacillus subtilis
Duez, Colette ULg; Vanhove, Marc; Gallet, Xavier et al

in Journal of Bacteriology (2001), 183(5), 1595-9

Penicillin-binding protein 4a (PBP4a) from Bacillus subtilis was overproduced and purified to homogeneity. It clearly exhibits DD-carboxypeptidase and thiolesterase activities in vitro. Although highly ... [more ▼]

Penicillin-binding protein 4a (PBP4a) from Bacillus subtilis was overproduced and purified to homogeneity. It clearly exhibits DD-carboxypeptidase and thiolesterase activities in vitro. Although highly isologous to the Actinomadura sp. strain R39 DD-peptidase (B. Granier, C. Duez, S. Lepage, S. Englebert, J. Dusart, O. Dideberg, J. van Beeumen, J. M. Frere, and J. M. Ghuysen, Biochem. J. 282:781-788, 1992), which is rapidly inactivated by many beta-lactams, PBP4a is only moderately sensitive to these compounds. The second-order rate constant (k(2)/K) for the acylation of the essential serine by benzylpenicillin is 300,000 M(-1) s(-1) for the Actinomadura sp. strain R39 peptidase, 1,400 M(-1) s(-1) for B. subtilis PBP4a, and 7,000 M(-1) s(-1) for Escherichia coli PBP4, the third member of this class of PBPs. Cephaloridine, however, efficiently inactivates PBP4a (k(2)/K = 46,000 M(-1) s(-1)). PBP4a is also much more thermostable than the R39 enzyme. [less ▲]

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See detailPurification and Characterization of the Heat-Labile Alpha-Amylase Secreted by the Psychrophilic Bacterium Tac 240b
Chessa, Jean-Pierre; Feller, Georges ULg; Gerday, Charles ULg

in Canadian Journal of Microbiology (1999), 45(6), 452-7

A total of 59 bacteria samples from Antarctic sea water were collected and screened for their ability to produce alpha-amylase. The highest activity was recorded from an isolate identified as an ... [more ▼]

A total of 59 bacteria samples from Antarctic sea water were collected and screened for their ability to produce alpha-amylase. The highest activity was recorded from an isolate identified as an Alteromonas species. The purified alpha-amylase shows a molecular mass of about 50,000 Da and a pI of 5.2. The enzyme is stable from pH 7.5 to 9 and has a maximal activity at pH 7.5. Compared with other alpha-amylases from mesophiles and thermophiles, the "cold enzyme" displays a higher activity at low temperature and a lower stability at high temperature. The psychrophilic alpha-amylase requires both Cl- and Ca2+ for its amylolytic activity. Br- is also quite efficient as an allosteric effector. The comparison of the amino acid composition with those of other alpha-amylases from various organisms shows that the cold alpha-amylase has the lowest content in Arg and Pro residues. This could be involved in the principle used by the psychrophilic enzyme to adapt its molecular structure to the low temperature of the environment. [less ▲]

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See detail- Purification and characterization of tomato leaf (Lycopersicon esculentum Mill.) hydroperoxide lyase.
Fauconnier, Marie-Laure ULg; Perez, A. G.; Sanz, C. et al

in Journal of Agricultural and Food Chemistry (1997), 45(11), 4232-4236

Hydroperoxide lyase (HPOOH lyase) was extracted from tomato leaves (Lycopersicon esculentum Mill.) and purified to apparent homogeneity by fractionated precipitation with polyethylene glycol 6000, ion ... [more ▼]

Hydroperoxide lyase (HPOOH lyase) was extracted from tomato leaves (Lycopersicon esculentum Mill.) and purified to apparent homogeneity by fractionated precipitation with polyethylene glycol 6000, ion exchange chromatography, and ultrafiltration. The enzyme is a trimer of 73 000 Da units with a molecular mass of 216 000 (determined by native-PAGE and gel filtration); its pI is around 4.9. Enzyme activity measurments realized with 9- and 13-hydroperoxides of linoleic acid (9-La OOH and 13-La OOH, respectively), R-linolenic acid (9-Ln OOH and 13-Ln OOH, respectively), and ç-linolenic acid (9-çLn OOH and 13-ç-Ln OOH, respectively) revealed a great affinity for 13-Ln OOH. The enzyme is rapidly inhibited by its substrate (13-Ln OOH), but preincubation with the other five hydroperoxides, which are not degraded by the enzyme, also resulted in activity inhibition. Dialysis could not restore the activity. When 13-Ln OOH is reduced in its corresponding alcohol or converted to its methyl ester, the inhibition is reduced. [less ▲]

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See detailPurification and characterization of Yarrowia lipolytica exracellular lipase.
Destain, Jacqueline ULg; Swiatkowski, T.; van Beumen, J. et al

Poster (1999, September)

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See detailPurification and cultivation of follicular dendritic cells.
Marcoty, C.; Heinen, Ernst ULg; Bosseloir, A. et al

in Lymphatic tissues and in vivo immune responses (1991)

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See detailPurification and Culture of Adult Rat Dorsal Root Ganglia Neurons
Delree, P.; Leprince, Pierre ULg; Schoenen, Jean ULg et al

in Journal of Neuroscience Research (1989), 23(2), 198-206

To study the trophic requirements of adult rat dorsal root ganglia neurons (DRG) in vitro, we developed a purification procedure that yields highly enriched neuronal cultures. Forty to fifty ganglia are ... [more ▼]

To study the trophic requirements of adult rat dorsal root ganglia neurons (DRG) in vitro, we developed a purification procedure that yields highly enriched neuronal cultures. Forty to fifty ganglia are dissected from the spinal column of an adult rat. After enzymatic and mechanical dissociation of the ganglia, myelin debris are eliminated by centrifugation on a Percoll gradient. The resulting cell suspension is layered onto a nylon mesh with a pore size of 10 microns. Most of the neurons, the diameter of which ranged from 17 microns to greater than 100 microns, are retained on the upper surface of the sieve; most of the non-neuronal cells with a caliber of less than 10 microns after trypsinization go through it. Recovery of neurons is achieved by reversing the mesh onto a Petri dish containing culture medium. Neurons to non-neurons ratio is 1 to 10 in the initial cell suspension and 1 to 1 after separation. When these purified neurons are seeded at a density of 3,000 neurons/cm2 in 6 mm polyornithine-laminin (PORN-LAM) coated wells, neuronal survival (assessed by the ability to extend neurites), measured after 48 hr of culture, is very low (from 0 to 16%). Addition of nerve growth factor (NGF) does not improve neuronal survival. However, when neurons are cultured in the presence of medium conditioned (CM) by astrocytes or Schwann cells, 60-80% of the seeded, dye-excluding neurons survive. So, purified adult DRG neurons require for their short-term survival and regeneration in culture, a trophic support that is present in conditioned medium from PNS or CNS glia.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailPurification and properties of the exocellular β-lactamase of Actinomadura strain R39
Duez, Colette ULg; Frère, Jean-Marie ULg; Ghuysen, Jean-Marie ULg et al

in Biochimica et Biophysica Acta - General Subjects (1982), 700

The exocellular beta-lactamase (penicillin amido-beta-lactamhydrolase, EC 3.5.2.6) of Actinomadura R39 consists of one single polypeptide chain of molecular weight about 15 200. It exhibits a highly ... [more ▼]

The exocellular beta-lactamase (penicillin amido-beta-lactamhydrolase, EC 3.5.2.6) of Actinomadura R39 consists of one single polypeptide chain of molecular weight about 15 200. It exhibits a highly asymmetrical shape, has a low isoelectric point (at pH 5.0) and contains about 9.3% (w/w) of a polydeoxyribonucleotide with which it forms a rather stable complex. Removal of a substantial amount of this deoxyribonucleotide by treatment with DNAase I has no effect on the enzyme activity. The beta-lactamase has a wide spectrum of activity. Penicillins and delta 3-cephalosporins can be either good or poor substrates. Oxacillin, which is a poor substrate of most beta-lactamases from Gram-positive bacteria, is a good substrate of the beta-lactamase of Actinomadura R39. Its best substrate, however, is nitrocefin (kcat/Km: 2300 000 M-1.s-1; catalytic centre activity: 210 s-1). The kcat/Km values observed with some penicillins and delta 3-cephalosporins are similar to the values of the bimolecular rate constants that govern the formation of the acyl-enzyme intermediates between these antibiotics and the serine D-alanyl-D-alanine peptidase that is also secreted by the same strain Actinomadura R39. Such a relationship, however, is not observed with all the beta-lactam compounds tested. [less ▲]

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See detailPurification and properties of the replicative form of Semliki Virus RNA
Osterrieth, P. M.; Rentier-Delrue, Françoise ULg; Calberg-Bacq, C. M. et al

in Hoppe Seyler's Zeitschrift für Physiologische Chemie (1974)

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See detailPurification de la [beta]-(1-4)-N-acétylhexosaminidase sécrétée par Streptomyces albus G et active sur les parois de Micrococus lysodeikticus
Dierickx, L.; Ghuysen, Jean-Marie ULg

in Biochimica et Biophysica Acta (1962), 58

The N-acetylhexosaminidase (referred as Str) secreted by Streptomyces albus G. has been purified by zone electrophoresis. It is slightly less basic than egg-white lysozyme. Its isoelectric point is close ... [more ▼]

The N-acetylhexosaminidase (referred as Str) secreted by Streptomyces albus G. has been purified by zone electrophoresis. It is slightly less basic than egg-white lysozyme. Its isoelectric point is close to pH 10.3. It has no action on the [alpha]- and [beta]-phenylglycosides of N-acetylglucosamine and on the disaccharides [beta]-(1-4)-di-N-acetylglucosamine (di-N-acetylchitobiose) and [beta]-(1-6)-N-acetylglucosaminyl-N-acetylmuramic acid but it splits the tetrasaccharide [beta]-(1-4)-tetra-N-acetylglucosamine(tetra-N-acetylchitotetraose) in di-N-acetylchitobiose. Contrary to lysozyme, it does not split the tetrasaccharide O-[beta]-N-acetylglucosaminyl-(1-6)-O-[beta]-N-acetylmuraminyl-(1-4)-O-[beta]-N-acetylglucosaminyl-(1-6)-[beta]-N-acetylmuramic acid in disaccharide by hydrolyzing the [beta](1-4) linkage. In those conditions the disaccharide liberated, as well as the tetrasaccharide, from Microccus lysodeikticus cell walls after incubation with the N-acetylhexosaminidase Str, can not be put down to a further digestion of some tetrasaccharidic fragments. A chitobiase only active on the [beta]-phenyl-glycoside of N-acetylglucosamine and on the di-N-acetylchitobiose is also present in contentrated culture filtrates. It is a protein acid at pH 6.6. [less ▲]

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See detailPurification de protéines associées à la gestation (PAG) chez le porc
Dethier, M.; Melo de Sousa, Noelita ULg; Balci, S. et al

Poster (2009)

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See detailPurification et caractérisation de la conductine au sodium
Grandfils, Christian ULg

Master's dissertation (1984)

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See detailPurification of a novel dehydrogenase : a vanillin : NAD(P) oxidoreductase.
Bare, G.; Moukil, M. A.; Swiatkowski, T. et al

Poster (1995, February)

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See detailPurification of active matrix metalloproteinase catalytic domains and its use for screening of specific stromelysin-3 inhibitors.
Kannan, R.; Ruff, M.; Kochins, J. G. et al

in Protein Expression & Purification (1999), 16

The matrix metalloproteinase (MMP) stromelysin-3 (ST3) has been shown to be involved in malignant tumor progression and therefore represents an attractive therapeutical target. In order to screen for ST3 ... [more ▼]

The matrix metalloproteinase (MMP) stromelysin-3 (ST3) has been shown to be involved in malignant tumor progression and therefore represents an attractive therapeutical target. In order to screen for ST3 synthetic inhibitors, we have produced and purified the catalytic domain of ST3, matrilysin, stromelysin-2, and membrane type-1 MMP from inclusion bodies in a bacterial system. Our strategy allowed the purification of MMPs directly in the active form, thereby avoidingin vitroactivation. A total of 140,000 synthetic compounds from the Bristol-Myers Pharmaceutical Research Institute chemical deck were tested, using a substrate-based colorimetric enzymatic assay, in which ST3 activity was evaluated through its ability to cleave and inactivate α-1 proteinase inhibitor. One ST3 inhibitor belonging to the cephalosporin family of antibiotics was thereby identified. [less ▲]

Detailed reference viewed: 75 (1 ULg)