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)

Enzyme selection is very important to establish enzyme immunoassay system. The appropriate enzyme selected to label an immunochemical reagent must have certain qualities as follows: 1) highly purified and high specific activity, 2) inexpensive, 3) stable during conjugation and for a long time in a proper storage condition, 4) easily conjugated, measured, and applied to highly sensitive assay. Several enzymes fulfill most of the above requirements and have been successfully used in enzyme immunoassay. These are horseradish peroxidase, alkaline phosphatase, beta-galactosidase, glucose oxidase, glucose-6-phosphate dehydrogenase, etc. As for enzyme activity measuring procedures, chemiluminescence and bioluminescence assays generally exhibit more sensitive detection limits than fluorescent or colorimetric assays. In the future, ultrasensitive luminescent assays and production of excellent recombinant enzymes are expected.
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PMID:[Properties of enzymes for enzyme immunoassay]. 747 74

The feasibility of using permeabilized whole cells as a source of intracellular enzymes instead of isolated expensive enzymes for the estimation of biomolecules has been studied. Alcohol dehydrogenase (ADH), glucose-6-phosphate dehydrogenase (G6PDH), hexokinase (HK), and beta-galactosidase (beta-GAL) activities of cetyltrimethylammonium bromide (CTAB)-permeabilized whole yeast cells were employed to estimate ethyl alcohol, glucose, and lactose. The method using permeabilized cells was comparable to that of isolated enzymes and was applicable for the estimation of these analytes in complex samples such as blood, milk, and fermented samples. The usefulness of permeabilized cells as a single source of more than one enzyme required for coupled enzyme assays was demonstrated.
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PMID:Detergent permeabilized yeast cells as the source of intracellular enzymes for estimation of biomolecules. 776 9

We discuss, from an industrial point of view, the scope and possibilities of recombinant DNA technology for "diagnostic enzyme" production and application. We describe the construction of enzyme-overproducing strains and show how to simplify downstream processing, increase product quality and process profitability, improve diagnostic enzyme properties, and adjust enzymes to harsh assay conditions. We also consider some safety and environmental aspects of enzyme production. Other aspects of diagnostic enzymes that we cover are the facilitation of enzyme purification by attachment of short amino acid tails, the introduction of tails or tags for site-specific conjugation or oriented immobilization, the construction of bi- or multifunctional enzymes, and the production of enzyme-based diagnostic tests as demonstrated by the homogeneous immunoassay system of CEDIA tests. We use as examples of diagnostic enzymes glucose-6-phosphate dehydrogenase (EC 1.1.1.49), glucose oxidase (EC 1.1.3.4), alkaline phosphatase (EC 3.1.3.1), alpha-glucosidase (EC 3.2.1.20), pyruvate oxidase (EC 1.2.3.3), creatinase (EC 3.5.3.3), and beta-galactosidase (EC 3.2.1.23).
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PMID:Enzymes in diagnostics: achievements and possibilities of recombinant DNA technology. 817 39

The pregnant rats were treated with formaldehyde (0.5 mg/kg daily per os) during whole period of pregnancy. The activity of cytochrome-c-oxidase, malate dehydrogenase, nucleotidase, glucose-6-phosphatase, beta-glucuronidase, N-acetyl-beta-glucosaminidase, beta-galactosidase, H(+)-ATPase, glutamate dehydrogenase, NAD- and NADP-isocitrate dehydrogenase, fructose-bisphosphate aldolase, glucose-6-phosphate dehydrogenase and content of protein in liver celts of offsprings (newborns, 2 weeks age and 2 months age) were studied. It was shown differences in development enzyme systems of control and experimental animals during ontogenesis.
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PMID:[Experimental study of the effect of formaldehyde during embryogenesis on the activity of rat liver enzyme systems in ontogenesis]. 913 53

GPD regulatory sequences were used to express a phleomycin resistance gene (Sh ble) in Schizophyllum commune, resulting in high numbers of phleomycin-resistant transformants. Attempts to express heterologous genes coding for hygromycin B phosphotransferase (hph), aminoglycoside phosphotransferase (apt), beta-glucuronidase (uidA) and beta-galactosidase (lacZ) using the same regulatory sequences were not successful and no mRNA could be detected. Cloning the hph and uidA genes in an internally deleted GPD gene resulted in truncated transcripts which ended within the 5'-parts of the heterologous genes. Cloning of the same genes as transcriptional fusions downstream from the Sh ble gene also resulted in truncated transcripts ending in the 5'-parts of these heterologous genes. It is suggested that AT-rich sequences in heterologous genes might be involved in generating these truncated transcripts, thereby preventing expression in S. commune.
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PMID:Expression of heterologous genes in Schizophyllum commune is often hampered by the formation of truncated transcripts. 950 4

The yeast Saccharomyces cerevisiae contains a flavohemoglobin, encoded by the gene YHB1, whose function is unclear. Previous reports presented evidence that its maximal expression requires disruption of mitochondrial respiration and that it plays a role in the response to oxidative stress. We have studied the expression of YHB1 in respiratory deficient cells and in cells exposed to various compounds causing oxidative stress. Several different strains and approaches (spectroscopic detection of the oxygenated form of Yhb1p, beta-galactosidase activity of a YHB1-lacZ fusion, and Northern blot analysis) were used to demonstrate that YHB1 expression and Yhb1p production are not increased by respiration deficiency. YHB1 expression was unchanged in cells challenged with antimycin A or menadione, while it decreased in cells exposed to H2O2, diamide, dithiothreitol, and Cu2+. Transcription of YHB1 is not under the control of the transcriptional factor Yap1p. These results do not support a participation of YHB1 in the genetic response to oxidative stress. We also analyzed the growth phenotypes associated with altered Yhb1p production using YHB1-deleted strains and strains that greatly overproduced Yhb1p. Yhb1p appears to protect cells against the damage caused by Cu2+ and dithiothreitol, while sensitizing them to H2O2. Yhb1p overproduction in a glucose-6-phosphate dehydrogenase-deficient mutant decreased its growth rate. These data indicate that there is a complex relationship(s) between Yhb1p function(s) and cell defense reactions against various stresses.
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PMID:Flavohemoglobin expression and function in Saccharomyces cerevisiae. No relationship with respiration and complex response to oxidative stress. 954 81

Parotid and mandibular saliva was obtained from red kangaroos by concurrent acetylcholine isoprenaline stimulation. Salivary proteins were separated by horizontal electrophoresis on either cellulose acetate or starch gels and assessed by specific staining techniques for 23 enzymes commonly found in mammalian tissues and body fluids. Parotid saliva was positive for acid phosphatase, alpha-amylase, carbonic anhydrase, glucose-6-phosphate dehydrogenase, sorbitol dehydrogenase and superoxide dismutase activities. Mandibular saliva was positive for alcohol dehydrogenase in addition to the above six enzymes. The kangaroo salivas lacked activity for alkaline phosphatase, beta-galactosidase and non-specific esterase which occur in saliva from some mammalian species.
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PMID:Enzyme activity in parotid and mandibular saliva from red kangaroos, Macropus rufus. 978 23

A multivariate model is proposed relating short-term biomarker measurements in Daphnia magna to chronic effects (21-d exposure) occurring at the population level (time to death, mean brood size, mean total young per female, intrinsic rate of natural increase, net reproductive rate, and growth). The results of the short-term exposure (48 h-96 h) to eight model toxicants (cadmium, chromium, mercury, tributyl tin, linear alkylsulfonic acid, sodium pentachlorophenolate, lindane, and 2,4-dichlorophenoxyacetic acid) on the following biomarkers were used for the multivariate model: digestive enzymes (amylase, cellulase, beta-galactosidase, trypsin, and esterase), enzymes of the intermediary metabolism (glycogen phosphorylase, glucose-6-phosphate dehydrogenase, pyruvate kinase, lactate dehydrogenase, and isocitrate dehydrogenase), cellular energy allocation (CEA) (protein, carbohydrate, and lipid content and electron transport activity), and DNA damage and antioxidative stress activity. Using partial least squares to latent structures (PLS), a two-component model was obtained with R2 of 0.68 and a Q2 value of 0.60 based on the combined analysis of a limited number of the 48- and 96-h biomarker responses. For the individual population-level responses, the R2 values varied from 0.66 to 0.77 and the Q2 values from 0.52 to 0.69. Energy-related biomarkers (cellular energy allocation, lipid contents, anaerobic metabolic activity--pyruvate kinase, and lactate dehydrogenase), combined with parameters related to oxidative stress (catalase) and DNA damage measured after 48 and 96 h of exposure, were able to predict long-term effects at higher levels of biological organization.
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PMID:A multivariate biomarker-based model predicting population-level responses of Daphnia magna. 1295 51

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

A population of Rhizobium leguminosarum biovar viceae symbiotic on the roots of a commercial pea (Pisum sativum cv. Maro) crop was sampled by extracting a total of 249 isolates from root nodules on nine plants. Another 104 isolates were obtained by using soil from the same site to inoculate test plants, and a further 86 isolates were similarly obtained from soil 20 m distant within the crop. Each isolate was characterized for mobility variants of the enzymes glucose-6-phosphate dehydrogenase, superoxide dismutase, and beta-galactosidase by polyacrylamide gel electrophoresis. All three enzymes were polymorphic, and there was a strong disequilibrium among them. Of the 15 observed combinations of alleles (electrophoretic types [ETs]), 12 were indistinguishable from those previously described for isolates from a site 25 km distant. ET frequencies were significantly different among isolates from nodules on primary roots as opposed to lateral roots. The population on each individual plant was very diverse, but ET frequencies were similar from plant to plant. The ETs nodulating the primary roots were almost, although not perfectly, mixed, since the incidence of the same ETs in adjacent nodules was only about twice that expected by chance. The two samples derived from soil had the same ET frequencies but were significantly different from the field nodule sample, although the level of diversity was similar and there were no new ETs.
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PMID:Rhizobium Population Genetics: Enzyme Polymorphism in Rhizobium leguminosarum from Plants and Soil in a Pea Crop. 1634 87


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