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)

A motility inhibiting factor (MIF) in sperm plasma membrane of mammalian spermatozoa (goat) has been demonstrated. This factor has been purified to apparent homogeneity by Sepharose-6B affinity chromatography and DEAE-cellulose ion-exchange chromatography. The molecular weight of the isolated factor has been estimated as 98 kDa by molecular sieving and analytical HPLC. SDS-polyacrylamide gel electrophoresis of MIF gave a single band of 100 kDa, indicating that the factor is a monomer. MIF is a thermo-stable factor and it inhibited the spermatozoa motility in a dose dependent manner. It is a glycoprotein as it binds with high affinity to Sepharose-6B and the affinity matrix-bound factor can be eluted with D-galactose. Data show that the motility inhibiting activity is lost completely when treated with beta-galactosidase indicating that its sugar side chain is essential for its activity. Addition of MIF antibody caused significant enhancement of forward motility of the caput and cauda-spermatoza. This antibody may thus be useful for solving some of the problems of human infertility due to low sperm motility. The motility inhibiting protein may also be useful as a vaginal contraceptive.
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PMID:Isolation and identification of a novel motility-inhibiting factor from goat cauda sperm plasma membrane. 1288 94

Cystic fibrosis is a common lethal genetic disease caused by functional absence of the cystic fibrosis transmembrane conductance regulator (CFTR). Although a candidate disease for in utero gene therapy, demonstration of potentially therapeutic levels of transgene expression in the fetal airways after minimally invasive gene delivery is a mandatory prerequisite before application of this approach in humans can be considered. We report here on the delivery of a beta-galactosidase expressing adenovirus directly to the airways of fetal sheep in utero using ultrasound-guided percutaneous injection of the trachea in the fetal chest. Injection of adenoviral particles to the fetal airways was not associated with mortality and resulted in low-level expression in the peripheral airways. However, complexation of the virus with DEAE dextran, which confers a positive charge to the virus, and pretreatment of the airways with Na-caprate, which opens tight junctions, increased transgene expression, and a combination of these two enhancers resulted in widespread and efficient gene transfer of the fetal trachea and bronchial tree. Using a percutaneous ultrasound-guided injection technique, we have clearly demonstrated proof of principle for substantial transgene delivery to the fetal airways providing levels of gene expression that could be relevant for a therapeutic application of CFTR expressing vectors.
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PMID:Widespread and efficient marker gene expression in the airway epithelia of fetal sheep after minimally invasive tracheal application of recombinant adenovirus in utero. 1468 99

The changes in activities of soluble beta-galactosidase and two forms of wall-bound beta-galactosidases extracted with NaCl and EDTA were investigated throughout the development of muskmelon (Cucumis melo L. cv Prince) fruits. DEAE-cellulose ion-exchange chromatography of soluble beta-galactosidase revealed the presence of two isoforms. Soluble isoform I was detected in all stages throughout the fruit development, whereas soluble isoform II appeared around 34 d after anthesis when fruit ripening initiated. Both NaCl- and EDTA-released beta-galactosidase activities also increased as ripening proceeded. The soluble and wall-bound forms behaved differently upon ion-exchange chromatography. Enzymological properties such as optimum pH, optimum temperature, K(m) values for p-nitrophenyl beta-d-galactopyranoside, and inhibition by metal ions were nearly similar in all forms. Molecular sizes of pectic polymers and hemicelluloses extracted from fruit mesocarp cell walls were shifted from larger to smaller polymers during ripening, as determined by gel filtration profiles. NaCl-released beta-galactosidase from cell walls of ripe fruits had the ability to degrade in vitro the pectin extracted from preripe fruit cell walls to smaller sizes of pectin similar to those that were observed in ripe cell walls in situ. Both soluble isoform I and II were able to degrade in vitro the 5% KOH-extractable hemicellulose from preripe fruit cell walls to sizes of molecules similar to those that were observed in ripe cell walls in situ. Soluble isoform I and the NaCl-released form from ripe fruits were able to modify in vitro 24% KOH-extractable hemicellulose from preripe cell walls to sizes of molecules similar to those that were observed in ripe fruits in situ.
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PMID:The Role of beta-Galactosidases in the Modification of Cell Wall Components during Muskmelon Fruit Ripening. 1665 23

Tomatoes (Lycopersicon esculentum L.) contained a high level of beta-galactosidase activity which was due to three forms of the enzyme. During tomato ripening, the sum of their activities remained relatively constant, but the levels of the individual forms of beta-galactosidase changed markedly. The three enzymes were separated by a combination of chromatography of DEAE-Sephadex A-50 and Sephadex G-100. During ripening of tomatoes, beta-galactosidases I and III levels decreased but the beta-galactosidase II level increased more than 3-fold. The three enzymes were optimally active near pH 4, and all were inhibited by galactose and galactonolactone. However, the enzymes differed in molecular weight, K(m) value with p-nitrophenyl-beta-galactoside, and stability with respect to pH and temperature. beta-Galactosidase II was the only enzyme capable of hydrolyzing a polysaccharide that was isolated from tomatoes and that consisted primarily of beta-1, 4-linked galactose. The ability of beta-galactosidase II to degrade the galactan and the increase in its activity during tomato ripening suggest a possible role for this enzyme in tomato softening.
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PMID:beta-Galactosidases in Ripening Tomatoes. 1666 71

Pectic polysaccharides from the roots of cucumber (Cucumis sativus L.) grown in liquid culture medium with or without calcium (1 mm CaCl(2)) were studied after extraction successively by hot water and Na hexametaphosphate solution. The Ca(2+) starvation-treatment caused a striking reduction in content of extracted pectic polysaccharide; from an equivalent weight of cell walls, only 33.1% of the control level was extracted from root cell walls of plants cultured under Ca(2+) deficiency. The extracted pectic polysaccharides were fractionated into neutral and acidic polymers by a DEAE-Sephadex column. The acidic polymers, which represented more than 76% of the yield, appeared to be a major fraction of extracted pectic polysaccharides. The changes of molecular size and glycosyl residue composition of this fraction were compared for the control and Ca(2+)-deprived samples. The results indicate that Ca(2+) deficiency caused structural changes which could involve both branching pattern and extent of contiguous galacturonosyl units in the water-solubilized pectic polysaccharides. Ca(2+) starvation also led to a notable decrease in molecular size of the hexametaphosphate-solubilized polysaccharides and, to a lesser extent, of the water-solubilized fraction as well. In addition, polygalacturonase activity in tissue homogenates increased remarkably with the Ca(2+) deficiency, whereas beta-galactosidase activity did not undergo a change. Thus, it appears that one major effect of Ca(2+) deprivation was to stimulate polygalacturonase activity, an effect which could be involved in the control of the breakdown of pectic polysaccharides in the cell walls.
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PMID:Pectic polysaccharide breakdown of cell walls in cucumber roots grown with calcium starvation. 1666 97

Trichoderma reesei FTKO-39 grown at 35 degrees C for 5 d on wheat bran supplemented with MgCl2 and lactose as the carbon source produced two isozymes of beta-galactosidase: BGT I and BGT II. These isozymes were partially purified on a DEAE-Trisacryl column. Both BGT I and BGT II fractions exhibited optimum activity at 65 degrees C, but the pH optima were 4.0 and 6.5, respectively. The isozymes also showed similar thermal stability. However, BGT I was more stable than BGT II in a pH range of 3.0-10.0. At least two different beta-galactosidases are produced by T. reesei, as revealed by the two bands seen on a 6% polyacrylamide gel stained for activity.
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PMID:Production of beta-galactosidase by Trichoderma reesei FTKO-39 in wheat bran: partial purification of two isozymes. 1670 8

1. Ten rat tissues and organs have been assayed for beta-galactosidase with phenyl beta-d-galactoside, p-nitrophenyl beta-d-galactoside, p-aminophenyl beta-d-galactoside and 4-methylumbelliferyl beta-d-galactoside as substrates. 2. The relative activities of these tissues are independent of the mode of assay, and maximum rates of hydrolysis are not greatly affected by the nature of the substrate. 3. Inhibition studies suggest the liver enzyme has no associated beta-glucosidase activity. 4. There is no cellular localization of preferential activity towards any of the four substrates in liver, kidney or spleen. 5. Evidence suggesting the non-destructive penetration of liver lysosomal membranes by p-nitrophenyl beta-d-galactoside is presented. 6. Liver lysosomal beta-galactosidase exists in multiple forms that can be separated on DEAE-cellulose, and the enzyme components that are bound to the membrane appear to be similar to those of the lysosome sap. 7. The chromatographic pattern of enzyme excreted in the urine is compared with those from the kidney, intestine, spleen and liver.
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PMID:Specificity and multiple forms of beta-galactosidase in the rat. 1674 24

Targeting gene therapy vectors to the fetal intestinal tract could provide a novel means toward prevention of the early postnatal intestinal pathology of cystic fibrosis and other conditions, such as congenital enteropathy, that cause intestinal failure. Among these conditions, cystic fibrosis is by far the most common lethal genetic disease. It is caused by a functional absence or deficiency of the cystic fibrosis transmembrane conductance regulator and manifests in the gut as meconium ileus. Prenatal treatment of genetic disease may avoid early-onset tissue damage and immune sensitization, and may target cells that are less accessible in the adult. We investigated gene transfer to the fetal gut, using a minimally invasive injection technique. First-generation replication-deficient adenoviral vectors encoding the beta-galactosidase gene and transduction-enhancing agents were injected into the stomach of early-gestation fetal sheep (n = 8, 60 days of gestation; term, 145 days) under ultrasound guidance. Reporter gene expression was observed 2 days after injection in the villi of the gastrointestinal epithelia after 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside staining and beta-galactosidase immunohistochemistry of fetal tissues. Expression of beta-galactosidase, as measured by enzyme-linked immunosorbent assay, was enhanced after pretreatment of the fetal gut with sodium caprate, which opens tight junctions, and after adenovirus complexation with DEAE-dextran, which confers a positive charge to the virus. Instillation of the fluorocarbon perflubron after virus delivery resulted in tissue transduction from the fetal stomach to the colon. Using a clinically relevant technique, we have demonstrated widespread gene transfer to the fetal gastrointestinal epithelia.
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PMID:Clinically applicable procedure for gene delivery to fetal gut by ultrasound-guided gastric injection: toward prenatal prevention of early-onset intestinal diseases. 1683 75

A stable and soapless latex of diethylaminoethyl-dextran-methyl methacrylate (DEAE-dextran-MMA) graft copolymer (DDMC) has been developed for nonviral gene delivery vectors that are possible to autoclave. DDMC relatively easily formed a polyion complex between DNA and DDMC by the hydrophobic force of graft poly(MMA) depending on its large positive entropy change (DeltaS). DDMC has been confirmed as having a high protection facility for DNase by DNase degradation test.Transfection activity was determined using the beta-galactosidase assay, and a higher value of 16 times or more was confirmed for the DDMC samples in comparison with one of the starting DEAE-dextran hydrochloride samples. The resulting DDMC, having an amphiphilic domain so as to form a polymer micelle, should become a stable latex with a hydrophilic-hydrophobic microseparated domain. The complex of DDMC and plasmid DNA may be formed on the spherical structure of the amphiphilic microseparated domain of DDMC and have a good affinity to the cell membrane. The infrared absorption spectrum shift to a high-energy direction at around 3450 cm(-1), because of the complexes between DNA and DDMC, may cause the formation of more compact structures, not only by a coulomb force between the phosphoric acid of DNA and the DEAE group of DEAE-dextran copolymer but also by a force from the multi-intermolecule hydrogen bond in the backbone polymer DEAE-dextran and a hydrophobic force from the graft poly(MMA) in DDMC. It is thus concluded that DNA condensation may possibly have a high transfection efficiency via DDMC. The high efficiency of this graft copolymer, which is sterilized by an autoclave, may thus make it a valuable tool for safe gene delivery.
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PMID:Characteristics of DEAE-dextran-MMA graft copolymer as a nonviral gene carrier. 1776 39

This report continues or examination of the effect of genetically engineered charge modifications on the partitioning behavior of proteins in aqueous two-phase extration. The genetic modifications consisted of the fusion of charged peptide tails to beta-galactosidase and charge-change point mutations to T4 lysozyme. Our previous article examined the influence of these charge modifications on partitioning as a function of interfacial potential difference. In this study, we examined charge directed partitioning behavior in PEG/dextran systems containing small amounts of the charged polymers diethylaminoethyl-dextran (DEAE-dextran) or dextran sulfate. The best results were obtained when attractive forces between the protein and polymer were present. Nearly 100% of the beta-galactosidase, which carries a net negative charge, partitioned to the DEAE-dextran-rich phase regardless of whether the phase was dextran or PEG. In these cases, cloudiness of the protein-rich phases suggest that strong charge interactions resulted in protein/polymer aggregation, which may have contributed to the extreme partitioning. Unlike the potentialdriven partitioning reported previously, consistent partitioning trends were observed as a result of the fusion tails, with observed shifts in partition coefficient (K(p)) of up to 37-fold. However, these changes could not be solely attributed to charge-based interactions. Similarly, T4 lysozyme, carrying a net positive charge, partitioned to the dextran sulfate-containing phase, and displayed four- to sevenfold shifts in K(p) as a result of the point mutations. These shifts were two to four times stronger than those observed for potential driven partitioning. Little effect on partitioning was observed when the protein and polymer had the same charge, with the exception of beta-galactosidase with polyarginine tails. The high positive charge density of these tails provided for a localized interaction with the dextran sulfate, and resulted in 2- to 15-fold shifts in K(p). (c) 1995 John Wiley & Sons, Inc.
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PMID:Genetically engineered charge modifications to enhance protein separation in aqueous two-phase systems: Charge directed partitioning. 1862 63


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