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 library of rabbit poxvirus DNA fragments contained in the expression cloning vector lambda gt11 was screened with monoclonal antibodies that react specifically against a 14-kilodalton envelope protein of vaccinia virus and rabbit poxvirus. The 14-kilodalton protein appears to play an important role in virus penetration at the level of cell fusion; it also elicits neutralizing antibodies, and it forms covalently linked trimers on the surface of virions and in infected cells (Rodriguez et al., J. Virol. 56:482-488, 1985; Rodriguez et al., J. Virol. 61:395-404, 1987). Two recombinant bacteriophages expressing beta-galactosidase fusion proteins were isolated. Restriction enzyme analysis and hybridization studies mapped the 14-kilodalton encoding sequences in the middle of vaccinia virus HindIII A DNA fragment. Nucleotide sequence analysis revealed an open reading frame (ATG) preceded by a characteristic TAA sequence of late genes. The sequence spans 330 nucleotides and codes for a protein with a molecular weight of 12,500 and an isoelectric point of 6.3. There are two small hydrophobic regions, one at the C terminus (11 amino acids) and the other at the N terminus (5 amino acids). The protein contains two cysteines for oligomer formation and one glycosylation site. Inspection of the deduced amino acid sequence of the 14-kilodalton protein revealed consensus sites with the hemagglutinin precursor of influenza A virus and with adenylate kinase and cytochrome c of various species.
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PMID:Mapping and nucleotide sequence of the vaccinia virus gene that encodes a 14-kilodalton fusion protein. 282 62

Yeast mitochondrial adenylate kinase (high molecular mass form, gene locus: AKY2) is encoded on chromosome IV of the same DNA strand as histone H2A-1. The nontranslated intergenic region spans 560 bp, the nontranscribed spacer can be estimated to comprise at most 300 bp. The TATA-box sequence is contained in a striking environment consisting of 20 alternating pyrimidines and purines. The AKY2 transcript is made constitutively: (i) the cellular mRNA concentration does not vary significantly with either growth conditions or elapse of the cell cycle; (ii) beta-galactosidase activity is about constant in yeast cells grown on various carbon sources after transformation with AKY2-promoter/lacZ fusions; (iii) primer elongation analysis shows that utilization of 5 initiation sites is qualitatively and quantitatively independent of the growth conditions and the carbon source used; (iv) Western blot analysis and adenylate kinase activity measurements indicate the absence of post-transcriptional controls as well.
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PMID:Yeast adenylate kinase is transcribed constitutively from a promoter in the short intergenic region to the histone H2A-1 gene. 284 62

The present investigations on rat lung show that metabolic changes occurring around the 20th gestational day are accompanied by multiple alterations in the quantitative pattern of enzymes. This involves increases in two lysosomal enzymes (N-acetyl beta-glucosaminidase and beta-galactosidase) and a rise and fall in pyruvate kinase and alpha-glucosidase. The striking transient upsurge of adenylate kinase, however, is postponed until after birth. The normal diminution of thymidine kinase and peptidylproline hydroxylase is drastically enhanced by an injection of cortisol to fetal rats. Studies on human pulmonary tissues consisted in determining enzyme concentration from the ninth to the 21st week of gestation and an histologically normal adult lungs. The results show that the 15th to the 21st week of gestation is the period of increase in pyruvate kinase, adenylate kinase and alpha-glucosidase. The rise during the development of several enzymes (e.g., 5'-nucleotidase, alkaline phosphatase, and gamma-glutamyl transpeptidase) and the decline in thymidine kinase and peptidylproline hydroxylase, however, dose not begin until after the 21st week of gestation.
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PMID:Phosphotransferases and lysosomal enzymes in fetal human and rat lung. 626 41

To develop reporter systems to study the regulation of protein degradation in innervated muscle, we have used strains of the nematode Caenorhabditis elegans containing transgenes that fuse lacZ or green fluorescent protein (GFP) coding regions to muscle-specific promoter/enhancer regions, such that the fusion proteins are expressed exclusively in body-wall and vulval muscle cells. The starvation-induced degradation of the beta-galactosidase reporter protein is quantitatively similar to that of two endogenous muscle proteins, arginine kinase and adenylate kinase. A soluble GFP in the muscle cytosol is degraded during starvation, but when GFP is fused to a full-length myosin heavy chain and incorporated into myofibrils, it is resistant to starvation-induced degradation. This suggests that under some conditions soluble muscle proteins may be extensively catabolized in preference to the proteins of the contractile fibers.
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PMID:Degradation of transgene-coded and endogenous proteins in the muscles of Caenorhabditis elegans. 1463 38

The Saccharomyces cerevisiae cell wall provides a semipermeable barrier that can retain intracellular proteins but still permits small molecules to pass through. When S. cerevisiae cells expressing E. coli lacZ are treated with detergent to extract the cell membrane, beta-galactosidase activity in the permeabilized cells is approximately 40% of the activity of the protein in cell extract. However, the permeabilized cells can easily be collected and reused over 15 times without appreciable loss in activity. Cell wall composition and thickness can be modified using different cell strains for enzyme expression or by mutating genes involved in cell wall biosynthesis or degradation. The Sigma1278b strain cell wall is less permeable than the walls of BY4742 and W303 cells, and deleting EXG1, which encodes a 1,3-beta-glucanase, can further reduce permeability. A short Zymolyase treatment can increase cell wall permeability without rupturing the cells. Encapsulating multiple enzymes in permeabilized cells can offer kinetic advantages over the same enzymes in solution. Regeneration of ATP from AMP by adenylate kinase and pyruvate kinase encapsulated in the same cell proceeded more rapidly than regeneration using a cell extract. Combining permeabilized cells containing adenylate kinase with permeabilized cells containing pyruvate kinase can also regenerate ATP from AMP, but the kinetics of this reaction are slower than regeneration using cell extract or permeabilized cells expressing both enzymes.
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PMID:Enzyme encapsulation in permeabilized Saccharomyces cerevisiae cells. 1505 89

During the final steps of epidermal differentiation, extracellular calcium ions enter keratinocytes and induce transglutaminase activity and cornified envelope formation. In other cell types, entry of calcium mediated by ionophores has been reported to induce exocytosis of lysosomes. In this study, we investigated whether lysosomes of keratinocytes might exhibit a similar behaviour. Ionomycin treatment induced cornified envelope formation in keratinocytes, but also morphological changes including plasma membrane blebbing, although no immediate alteration in cell viability could be detected. The activity of the soluble lysosomal enzymes cathepsin C and beta-galactosidase in the culture medium was increased upon ionomycin treatment. Cell leakage did not seem to be responsible for this phenomenon, as suggested by measurements of the cytosolic enzymes adenylate kinase and dipeptidylpeptidase III in the culture medium. Metabolic labelling followed by immunoprecipitation showed that ionomycin induced release of cathepsin D into the culture medium. Simultaneously, lysosome-associated membrane proteins (Lamps) 1 and 2 were detected at the cell surface of ionomycin-treated keratinocytes by biochemical and morphological approaches. These results suggest that upon ionomycin treatment, calcium entry stimulates exocytosis of lysosomes in keratinocytes.
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PMID:Calcium entry into keratinocytes induces exocytosis of lysosomes. 1512 11