Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The N-linked oligosaccharide moieties of sycamore (Acer pseudoplatanus L.) laccase are known to be highly heterogeneous. We confirmed that this oligosaccharide heterogeneity was caused not only during the oligosaccharide biosynthesis in Golgi apparatus, but also after the excretion of laccase protein into a culture medium. The culture medium for the sycamore cells (Acer pseudoplatanus L.) contained beta-galactosidase, alpha-L-fucosidase, beta-N-acetylglucosaminidase, alpha-mannosidase and beta-xylosidase activities. We showed that the largest sugar chain in laccase, oligosaccharide F, [formula: see text] was degraded to [formula: see text] by a crude exoglycosidase mixture in the culture medium.
 ...
PMID:Occurrence of heterogeneity of N-linked oligosaccharides attached to sycamore (Acer pseudoplatanus L.) laccase after excretion. 848 57

The amplification cycle consisting of NADH independent oligosaccharide dehydrogenase (ODH) and laccase has been recently reported to be highly sensitive to several catecholamines and p-aminophenol. A competitive immunoassay for 2,4-dichlorophenoxyacetic acid has been developed by combining this amplification cycle with beta-galactosidase as enzyme label resulting in p-aminophenol as product. The combination of enzymatic amplification cycles with a competitive immunoassay yields a highly sensitive measurement of 2,4-dichlorophenoxyacetic acid. Using a monoclonal antibody the linear range of the assay was between 0.02 and 100 ng/l and the c(50) was found at 0.2 ng/l; the detection limit was at 5 pg/l (25 fmol/l) corresponding to 5 amol.
 ...
PMID:High sensitive competitive immunodetection of 2,4-dichlorophenoxyacetic acid using enzymatic amplification with electrochemical detection. 1504 3

Commercial mushroom tyrosinase contains other proteins, enzymes, carbohydrates, and phenolic material besides tyrosinase. Carbohydrate and phenolic material comprise a large percentage of the powder resuspensions derived from Agaricus bisporus. Enzyme assays identified the presence of tyrosinase, laccase, beta-glucosidase, beta-galactosidase, beta-xylosidase, cellulase, chitinase, xylanase, and mannanase in the commercial tyrosinase. Protein sequencing indicated the presence of tyrosinase, a lectin, and a putative mannanase as well as 10 unidentified protein/peptides in the commercial tyrosinase preparations. Characteristics of tyrosinase isoforms were similar in two different commercial tyrosinase sources. Inhibition studies indicated that I 50 values for some tyrosinase inhibitors were different when the crude powder was compared to a partially purified tyrosinase. The presence of these contaminants has the potential to affect studies using commercial tyrosinase.
 ...
PMID:Enzyme, protein, carbohydrate, and phenolic contaminants in commercial tyrosinase preparations: potential problems affecting tyrosinase activity and inhibition studies. 1850 Aug 13

The relationship between the physiological state of fungi and the response of their functional system to metals is not known, limiting the use of fungal enzymes as tools for assessing metal ecotoxicity in terrestrial ecosystems. The present study attempts to establish how the development phases modulate the secretion of enzymes in the filamentous fungus Trametes versicolor after exposure to Cu. For that purpose, extracellular hydrolases (acid and alkaline phosphatases, aryl-sulfatase, beta-glucosidase, beta-galactosidase, and N-acetyl-beta-glucosaminidase) and oxidoreductases (laccase, manganese and lignin peroxidases) were monitored in liquid cultures for 2 weeks. Copper was added during either the growth or the stationary phases at 20 or 200 ppm. Results of the present study showed that Cu at the highest concentration modifies the secretion of enzymes, regardless of the development phase to which the fungus was exposed. However, the sensitivity of enzyme responses to Cu depended on the phase development and the type of secreted enzyme. In a general way, the production of hydrolases was decreased by Cu, whereas that of oxidoreductases was highly increased. Furthermore, lignin peroxidase was not detected in control cultures and was specifically produced in the presence of Cu. In conclusion, fungal oxidoreductases may be enzymatic biomarkers of copper exposure for ecotoxicity assessment.
 ...
PMID:Insights into the development of fungal biomarkers for metal ecotoxicity assessment: case of Trametes versicolor exposed to copper. 2082 20

Yeast's extracellular expression provides a cost-efficient means of producing industrially useful recombinant proteins. However, depending on the protein to be expressed, the production results in a poor yield, which is occasionally accompanied with loss of the expression plasmid and hence hampered growth of the host in the inducing medium. Here we propose an alternative approach, high cell-density expression, to improve the yield of a certain range of so-called difficult-to-express proteins. In this expression system, recombinant yeast cells resting in stationary phase (OD(660)=3-4) are suspended in a small aliquot of inducing medium to form a high cell-density culture (e.g., OD(660)=15). When applied to the yeast strains harboring Lentinula edodes laccase (Lcc1 or Lcc4) expressing plasmids, the high cell-density system allowed the host cells to synthesize elevated amounts of the laccase which resulted in >1000- to 6000-fold higher yield than those synthesized in a classical growth-associated manner. The resting cells required aerobic agitation for the maximum production. The production system also worked for other foreign enzymes but not for beta-galactosidase from Aspergillus oryzae or Escherichia coli, likely suggesting an involvement of chaperons that act on a certain range of secretory proteins.
 ...
PMID:High cell-density expression system: a novel method for extracellular production of difficult-to-express proteins. 2207 42