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)

Membrane vesicles can be prepared from murine lymphoid cells by nitrogen cavitation and fractionated by sedimentation through nonlinear sucrose density gradients. Two subpopulations of membrane vesicles, PMI and PMII, can be distinguished on the basis of sedimentation rate. The subcellular distribution of adenylate and guanylate cyclases in these membrane subpopulations have been compared with the distribution of a number of marker enzymes. Approximately 20-30% of the total adenylate and guanylate cyclase activity is located at the top of the sucrose gradient (soluble enzyme), the remainder of the activity being distributed in the PMI and PMII fractions (membrane-bound enzyme). More than 90% of the 5'-nucleotidase and NADH oxidase activities detected in lymphoid cell homogenates are located in PMI and PMII fractions, whereas succinate cytochrome c reductase activity is detected only in the PMII fractions. In addition, beta-galactosidase activity is distributed in the soluble and PMII fractions of the sucrose density gradients. On the basis of the fractionation patterns of these various enzyme activities, it appears that PMI fractions contain vesicles of plasma membrane and endoplasmic reticulum, whereas PMII fractions contain mitochondria, lysomes, and plasma membrane vesicles. Approximately 30-40% of the adenylate and guanylate cyclase activities in PMII can be converted to a PMI-like form following dialysis and resedimentation through a second nonlinear sucrose gradient. Adenylate and guanulate cyclases can be distinguished on the basis of sensitivity to nonionic detergents.
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PMID:The subcellular distribution of adenylate and guanylate cyclases in murine lymphoid cells. 0 90

Human adult lung fragments removed from macroscopically undamaged and anthracosis exempted zones of lungs of 20 pneumonectomies made for cancer, were tested for 25 enzymic activities. The location and intensities of these enzymic activities were different in the lung tissue components; The bronchial epithelia contained highly active LDH, MDH, SDH, NADH-TR and NADPH-TR, glucose-6-phosphate dehydrogenase, active hydroxyproline-2-epimerase, alkaline phosphatase. Ca2+-activated ATP-ase, and beta-galactosidase. Bronchial and vascular muscles presented intense activities of LDH, MDH and SDH of alkalinephosphatase, AMP-ase and Ca2+-activated ATP-ase, as well as of beta-galactosidase. The alveolar walls presented high activities of SDH, MDH and LDH, of alkaline and acid phosphatases, of beta-galactosidase and of Tween-40 and 60-esterases, of HEP, cytochrome-oxidase and peroxidase. The free alveolar macrophages were active for LDH, MDH, SDH, NADH-TR and NADPH-TR, G1-6-ph-DH, acid and alkaline phosphatase, cytochrome-oxidase and peroxidase, HEP, AMP-ase and Mg2+-activated ATP-ase, Tween-esterases, naphthol-ASD-acetate esterase, and beta-galactosidase. The endothelia contained high activities of alkaline phosphatase, of AMP-ase and Mg2+-activated ATPase, of LDH, MDH and SDH, and of beta-galactosidase. In bronchial lymphoid nodules it was the LDH, MDH, SDH, cytochrome-oxidase and peroxidase, HEP, alkaline phosphatase and AMP-ase, Tween-60-esterase and beta-galactosidase that were active. The interlobular areas of the lung presented intense activities of SDH, MDH, LDH, HEP and cytochrome-oxidase. The activities of the other tested enzymes were weaker or absent in the adult human lung components, the same as those of aminopeptidases which were present only in some free alveolar macrophages. The discussion of some relationships between these enzymic actitivies and the morphology of the human adult lung tissue asserted that the latter could not be considered as a "normal" tissue but as one overstrained by the components of blood and polluted air.
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PMID:Histoenzymology of the lung. I. Enzyme activities of the lung tissue of acult humans; relationships between structure and functions. 14 Mar 14

Several lysosomal enzyme activities in cultured lymphoid cell lines were studied during 3 phases of cell culture; logarithmic growth phase, stationary phase and decline phase. Enzyme induction during cell growth was found in N-acetyl-hexosaminidase, beta-galactosidase and alpha-L-fucosidase, but no induction in alpha-D-mannosidase, alpha-glucosidase and beta-glucuronidase. The latter two enzymes were unchanged during all cell culture phases. A drop in alpha-L-fucosidase and alpha-D-mannosidase activity was found during the stationary and decline phases of cell culture.
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PMID:Lysosomal enzyme activities in cultured lymphoid cell lines. 41 May 67

The authors present the results of study or fegularities attending the changes in the activity of free, total and bound fractions of the lysosomal enzymes--beta-glucosidase and beta-galactosidase in the thymus and the spleen of rabbits under conditions of DOCA administration. The activity of the enzymes was studied 30 min, 1, 4, 12, 24 and 48 hours after a single injection of the hormone. DOCA administration caused biphasic changes in the activity of both glycosidases. A marked increase in the activity of all the enzyme fractions during the first experimental hours was later replaced by their fall. An increase in the activity of glycosidases at the early periods of DOCA administration pointed to the intensification of the enzymatic synthesis, and also could be associated with the spicific induction of the enzymatic activity. The activity of beta-glucosidase and of beta-galactosidase directly depended on DOCA dose. Effects similar to the experiments in vivo were obtained in vitro. The activity of hyaluronidase under the effect of Dca decreased considerably in the thymus and the spleen, particularly at the early experimental periods, pointing to reduction of tissue permeability of the lymphoid organs.
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PMID:[The effect of desoxycorticosterone acetate on the activity of the lysosomal enzymes of lymphoid organs]. 113 80

A two-site sandwich fluorescent-ELISA was optimized for the detection of HIV-1 p24 antigen produced by lymphoid cells infected with HIV-1 in vitro. To improve the sensitivity of the ELISA, a combination of streptavidin-beta-galactosidase and a fluorogenic substrate (4-methylumbelliferyl-beta-D-galactopyranoside) was employed for the enzymatic detection stage. Using recombinant p24 as standard antigen, a two-step assay detected as little as 0.7 pg/ml (3.10(-14) M) with an upper limit of 10,000 pg/ml. This detection range (approx. 50-70-times greater than ELISAs using a chromogenic detection) permitted an accurate and straightforward quantitation of p24 in culture supernatants. Overall, the fluorescent-ELISA had increased detectability, sensitivity and efficiency over existing ELISAs for HIV-1 p24.
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PMID:Development of a sensitive ELISA for HIV-1 p24 antigen using a fluorogenic substrate for monitoring HIV-1 replication in vitro. 143 56

A recombinant nonreplicating retroviral vector bearing the Escherichia coli lacZ indicator gene was used to mark a population of B cells in situ in murine lymphoid tissue. The retrovirus was surgically injected into popliteal lymph nodes during the primary immune response to DNP-CGG when B cell proliferation in the germinal centers was maximal. LacZ+ cells were initially detected in the perivascular medullary interstitium, where they expanded and persisted up to 2 weeks following retrovirus injection. Migrant lacZ+ B cells were detected in the spleen 3-18 weeks following immunization and resided in the red pulp or marginal zones. Two-color flow cytometric analysis using a fluorogenic substrate for beta-galactosidase revealed that lacZ+ cells bear kappa light chains and that at least 50% of these cells bound the hapten, DNP. Based on their location, life span, migratory capacity, antigenic specificity, and surface immunoglobulin density, lacZ+ cells define a distinct nonfollicular B cell population associated with other late developmental stages of B lymphocytes, including memory and plasma cells.
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PMID:In situ lacZ retrovirus-marked lymphocytes define a B cell microenvironment in the lymph node medulla. 151 19

A quantitative bioassay for human immunodeficiency viruses has been developed on the basis of the ability of the tat gene to transactivate the expression of an integrated beta-galactosidase gene in a HeLa-CD4+ cell line. Infection by a single virion of HIV-1 or HIV-2 corresponds to a unique blue syncytium or a cell cluster detected after fixation and addition of 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (a beta-galactosidase substrate). The number of infected lymphoid cells in a culture (stimulated human peripheral blood lymphocytes and cell lines) can also be quantified by cell-to-cell transmission of HIV into the HeLa-CD4(+)-beta-galactosidase monolayer. Infections by simian immunodeficiency viruses are similarly detected. This assay has been used to determine the dose response of drugs, the half-life of HIV at 37 degrees C, and the appearance of infectious particles after virus infection.
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PMID:Activation of a beta-galactosidase recombinant provirus: application to titration of human immunodeficiency virus (HIV) and HIV-infected cells. 211 May 96

In this report we describe the use of recombinant retroviruses to characterize the activity of an exogenous promoter in primary cells obtained from patients with lymphoproliferative disorders. The infection of a variety of cultured and primary lymphoid cells with a recombinant retrovirus containing a histone promoter-driven beta-galactosidase gene is shown to result in the expression of beta-galactosidase in 50% to 100% of the cells. A similar infection with a recombinant retrovirus containing the beta-galactosidase gene with an adenovirus E2 promoter, results in beta-galactosidase activity in a limited number of cultured and primary cells. Since the adenovirus E2 promoter has been well characterized and is known to be regulated by transactivators encoded by many viruses, the activity of this promoter in specific cell types is discussed in reference to both the biology of the cell and the possible presence of as yet undetected viral gene products.
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PMID:Retroviral mediated transfer and expression of exogenous genes in primary lymphoid cells: assaying for a viral transactivator activity in normal and malignant cells. 214 77

We describe two retroviral vector-based recombination substrate systems designed to assay for lymphoid VDJ recombinase activity in cultured cells. Both substrates incorporate a constitutive dominant marker gene (the simian virus promoter-driven neo gene) to allow selection of cells that stably integrate the substrate. Both substrates also include a second marker gene that becomes transcriptionally active only when inverted by a site-specific recombination event between flanking immunoglobulin variable-region gene segments. The first vector, similar in structure to previous retrovirus-based recombination substrates, utilizes the bacterial guanine-xanthine phosphoribosyltransferase gene (gpt) as its activatable marker; detection of inversion (VDJ recombinase activity) involves drug selection and Southern blotting analyses. We have used this vector to make a more extensive and quantitative survey of VDJ recombinase activity in B-lineage cell lines than has previously been performed with stable substrates, and we have compared our results with those of other studies that use transient recombination substrates. In the second vector, the activatable gene is the bacterial beta-galactosidase gene (lacZ). Detection for inversional activation of this gene is achieved by a fluorogenic assay, termed FACS-Gal, that detects beta-galactosidase activity in viable cells. The latter assay has the unique advantage of rapidly detecting cells that undergo recombination and also allows viable sorting of cells on the basis of the presence or absence of VDJ recombinase activity. We have used the lacZ vector to rapidly quantitate VDJ recombinase activity in B-lineage cell lines and compared the results with those obtained with the gpt vector. We have also used the lacZ vector to isolate variant pre-B-cell lines with low and high levels of VDJ recombinase activity.
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PMID:A novel fluorescence-based system for assaying and separating live cells according to VDJ recombinase activity. 232 7

This paper reports the identification of the lyn gene product, a member of the src-related family of protein-tyrosine kinases, and its expression in hematopoietic cells. A lyn-specific sequence (Arg-25 to Ala-119 of the protein) was expressed in Escherichia coli as a fusion protein with beta-galactosidase. Antiserum raised against the fusion protein immunoprecipitated a 56-kDa protein from human B lymphocytes. Incubation of the immunoprecipitate with [gamma-32P]ATP resulted in the phosphorylation of this protein at tyrosine residues. Immunohistological and immunoblotting analyses showed that the lyn gene product was expressed in lymphatic tissues (spleen and tonsil) and in adult lung, which contains many macrophages. Furthermore, both the transcripts and the protein products of the lyn gene accumulated in macrophages/monocytes, platelets, and B lymphocytes but were not expressed appreciably in granulocytes, erythrocytes, or T lymphocytes, suggesting that lyn gene products function primarily in certain differentiated cells of lymphoid and myeloid lineages.
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PMID:Selective expression of a protein-tyrosine kinase, p56lyn, in hematopoietic cells and association with production of human T-cell lymphotropic virus type I. 250 53


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