Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The use of a new substrate 2-(2-(4-(beta-D-galactopyranosyloxy)-3- methoxyphenyl)-vinyl)-3-methylbenzothiazolium toluene-4-sulphonate (VB-zTM-gal) is described for the detection of beta-galactosidase activity in colonies of wild type and mutant strains of Escherichia coli. On enzymic hydrolysis this substrate, which is soluble in water, released a chromophore which is red at pH 7 and bound to cellulose and nitrocellulose. The best procedure for the detection of activity was to grow colonies on standard nitrocellulose membranes (pore size 0.45 microns) laid onto an agar plate and to float the membranes over a solution of the substrate. Coloured colonies developed within 3 min, which were stable at 4 degrees C for several days, and this identified the expression of beta-galactosidase activity. This was found to be more specific than methods using triphenyltetrazolium or Eosin Methylene Blue media, and more economical than methods using X-gal (5-bromo-4-chloro-3-indolyl beta-D-galactopyranoside). VBzTM-gal should have applications in gene cloning technology and in the detection of coliform organisms in polluted water.
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PMID:Improved methods for the detection of beta-galactosidase activity in colonies of Escherichia coli using a new chromogenic substrate: VBzTM-gal (2-(2-(4-(beta-D-galactopyranosyloxy)-3-methoxyphenyl)-vinyl)-3- methylbenzothiazolium toluene-4-sulphonate). 190 79

Surface-activated silicas with methacrylate double bonds were introduced into a reaction medium where copolymerization of 1-vinyl-2-pyrrolidone (VP) and maleic anhydride (MA) took place. The copolymerization led to the formation of non-alternating copolymers of VP and MA. Each macromolecule of this copolymer consisted of alternately arranged regulated long sequences of VP units and single units of MA. The possibility for covalent bonding of beta-galactosidase to the MA units at different lengths of the VP sequences was studied. The content of coupled enzyme, as well as its activity, pH dependence and stability were determined.
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PMID:Coated reactive carriers based on copolymers of 1-vinyl-2-pyrrolidone and maleic anhydride for immobilization of enzymes. 884 65

We have developed protective interactive noncondensing (PINC) polymers, such as poly(N-vinyl pyrrolidone) (PVP) and poly(vinyl alcohol) (PVA), to protect plasmids from extracellular nuclease degradation while allowing the flexible complex to diffuse throughout the muscle tissue. Molecular modeling, zeta potential modulation, and ethidium bromide intercalation studies were performed to assess the mechanism of interaction between PVP and plasmid. The effect of salt concentration, pH, and polymer-plasmid ratios were investigated. We have correlated these variables with beta-galactosidase (beta-gal) expression after intramuscular administration to rats. PVP can form hydrogen bonds with the base pairs within the major groove of DNA at pH 4.0. The PVP-plasmid interaction results in a complex that is more hydrophobic (less negatively charged) than the uncomplexed plasmid due to the vinyl backbone of PVP. Up to a ten-fold enhancement in gene expression in rat muscle over the use of 'naked' DNA has been demonstrated using these systems. A linear structure-activity relationship (SAR) was found between the percent vinyl pyrrolidone monomer content in poly (vinyl pyrrolidone-covinyl acetate) polymers and beta-gal expression in muscle. Modulation of the interaction between PINC polymers and plasmid directly impacts the levels of gene expression in vivo. The linear SAR is being used to design novel PINC polymers with enhanced binding affinity to plasmids.
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PMID:Protective interactive noncondensing (PINC) polymers for enhanced plasmid distribution and expression in rat skeletal muscle. 968 49

Poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) is a water-soluble cationic polymer, which is able to bind to DNA by electrostatic interactions. At a polymer/plasmid ratio above 2 (w/w) positively charged complexes were formed with a size around 0.2 microm. The transfection efficiency of polymer/plasmid complexes was evaluated in cell culture (COS-7 and OVCAR-3 cells) using a pCMV-lacZ plasmid, encoding for beta-galactosidase, as a reporter gene. The optimal transfection efficiency was found at a PDMAEMA/plasmid ratio of 3-5 (w/w). Under these conditions 3-6% of the cells were actually transfected. Like other cationic polymers, PDMAEMA is slightly cytotoxic. This activity was partially masked by complexing the polymer with DNA. A pronounced effect of the molecular weight of the polymer on the transfection efficiency was observed. An increasing molecular weight resulted in an increasing number of transfected cells. Dynamic light scattering experiments showed that high molecular weight polymers (Mw>300 kDa) were able to condense DNA effectively (particle size 0.15-0.20 microm). In contrast, when plasmid was incubated with low molecular weight PDMAEMA, large complexes were formed (size 0.5-1.0 microm). Copolymers of DMAEMA with methyl methacrylate (MMA), ethoxytriethylene glycol methacrylate (triEGMA) or N-vinyl-pyrrolidone (NVP) also acted as transfection agents. A copolymer with 20 mol % of MMA showed a reduced transfection efficiency and a substantial increased cytotoxicity compared with a homopolymer of the same molecular weight. A copolymer with triEGMA (48 mol %) showed both a reduced transfection efficiency and a reduced cytotoxicity, whereas a copolymer with NVP (54 mol %) showed an increased transfection efficiency and a decreased cytotoxicity as compared to a DMAEMA homopolymer.
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PMID:2-(Dimethylamino)ethyl methacrylate based (co)polymers as gene transfer agents. 974 22

We have developed defective herpes simplex virus 1 (HSV-1) vectors, based on amplicon plasmids with a replication-deficient mutant, as helper for the transfer of the glutamic acid decarboxylase (GAD67) or beta-galactosidase (beta-gal) gene as control directed by HCMV promoter into neuronal-like cells (PC12) and primary neurons. GAD67 protein was detected immunochemically, while GAD67 activity in virus-producing and nonproducing cell lines was detected enzymatically or by GABA release. Infection with GAD67-expressing amplicon vectors enhanced the resistance of PC12 cells to H(2)O(2). This protection was related to increased energy metabolism, as shown by MTT reduction and ATP level, and involved the GABA shunt, as shown by the reduction in ATP level seen in the presence of gamma-vinyl GABA (GVG), a specific GABA transaminase inhibitor. Level of glutathione (GSH), which requires ATP for its synthesis, was increased by the GAD67 transgene. The activity of glucose-6-phosphate dehydrogenase involved in the maintenance of the NADPH that can be used for the regeneration of the GSH pool, was increased by infection with amplicon vectors. Thus, replication-deficient HSV-1 and the GAD67 transgene have complementary neuroprotective effects and infection with GAD67-expressing amplicon vectors was able to protect nondifferentiated cortical neurons from glutamate toxicity mediated by oxidative stress. Such defective GAD67-expressing HSV-1, as neurotropic vector, should be helpful in neurodegenerative diseases implicating alterations of energy metabolism and oxidative stress in neuronal cells expressing GABA transaminase.
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PMID:Enhancement of neuronal protection from oxidative stress by glutamic acid decarboxylase delivery with a defective herpes simplex virus vector. 1463 8

We present a simple approach for on-line concentration of SDS-protein complexes by using poly(vinyl alcohol) (PVA) solution in CGE. In comparison to the coated capillary, the presence of EOF in CGE omitted the need to fill the capillaries with polymer solutions prior to the analysis. More importantly, we found that highly reproducible separation of eight proteins by 3.5% PVA was achieved between runs and without the regeneration of high bulk EOF; the RSD of migration times was less than 0.7%. To further improve the concentration sensitivity, neutral PVA was introduced into the capillary with the help of EOF to act as sieving matrix. The occurrence of stacking at the boundary between the PVA and the sample zone is mainly due to the retardation of proteins by PVA. As a result, the LODs at an S/N of 3 for SDS-protein complexes are of the order of sub-nM to several nM. For example, the LOD for BSA is 0.78 nM, which is a 91-fold sensitivity enhancement over the normal injection. In addition, our stacking method has been applied to the analyses of proteins in Escherichia coli cells. The peak for beta-galactosidase (E. coli) was observed after 0.1 microM beta-galactosidase was spiked into the E. coli samples.
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PMID:On-line concentration of proteins by SDS-CGE with LIF detection. 1808 Feb 47

Two synthesis methods of poly(methyl vinyl ether-co-maleic anhydride) (Gantrez AN 119) nanoparticles (NP) (used for oral vaccination) were compared. Wheat germ agglutinin (WGA) was used as ligand to enhance the bioadhesive properties of NP and beta-galactosidase as antigen. The first method encapsulated beta-galactosidase in NP by co-precipitation in an acetone/water mixture containing 44% acetone. In the second method, antigen addition occurred in 100% acetone. To improve stability, NP were crosslinked with 1,3-diaminopropane. The stability of WGA-conjugated NP with encapsulated antigen diminished at lower pH and when decreasing the amount of crosslinker. The binding type between WGA and polymer depended on the synthesis method: predominantly ionic bonds were formed using the 44% acetone method, whereas synthesis via the 100% acetone method resulted in covalent bonds. The biological activity of the WGA coating, evaluated via a pig gastric mucin binding test, was lower in NP prepared via the 100% acetone method. No release of native antigen was detected after hydrolysis of NP, due to the covalent antigen binding during antigen encapsulation and the high reactivity of the polymer. Moreover, the mucosal irritation capacity was evaluated upon nanoparticle hydrolysis using a slug mucosal irritation assay. Herein, hydrolysed NP of the 44% acetone method were classified as mild irritative.
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PMID:Influence of reaction medium during synthesis of Gantrez AN 119 nanoparticles for oral vaccination. 1981 32

It is well known that biomaterials play an important role in the regulation of adhesion and growth of a variety of cultured cell types. However, whether biomaterials are associated with the senescence of cultured cells is not known. The present work shows that the decrease of the hydrophobic property of poly (ethylene-co-vinyl alcohol) (EVAL) from 44 mole% to 27 mole% ethylene could induce characteristic senescence-associated phenotypic changes such as larger cell shape, re-organized actin cytoskeleton, lower proliferation capacity, higher levels of senescence-associated beta-galactosidase (SA beta-gal) activity, and upregulation of the cell-cycle inhibitor p53 and its transcriptional target p21 in the cultured human diploid fibroblasts (HDFs). Furthermore, it was found that the cultured cells recovered their ability to grow when the substrate was reused every passage. It seemed that the extracellular matrix (ECM) proteins adsorbed onto the EVAL surface might have a protective role in the cellular aging process. Therefore, whether a biomaterial strongly influences cellular aging process must be considered in the selection of a biomaterial for the biomedical application.
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PMID:The effect of poly (ethylene-co-vinyl alcohol) on senescence-associated alterations of human dermal fibroblasts. 1995 40

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