A-Galactosidase Activity

Application and Principle Use this procedure to determine a-galactosidase activity in enzyme preparations derived from Aspergillus niger var. The assay is based on a 15-min hydrolysis of p-nitrophenyl-a-D-galactopyranoside followed by spec-trophotometric measurement of the liberated p-nitrophenol. 

Catalase Activity, 791 Cellulose Activity, 791 Chymotrypsin Activity, 793 Diastase Activity (Diastic Power), 793 a-Galactosidase Activity, 794 [i-Glucanasc Activity, 795 Glucoamylase Activity... 

Mapes, C.A., Sweeley, C.C. Preparation and properties of an affinity column adsorbent for differentiation of multiple forms of a-galactosidase activity. J. biol. Chem. 248, 2461-2470 (1973)... 

Fig. 6.6A, B. (A) Changes in total -mannanase activity in germinated carob (x), lucerne ( ) and soybean (o) seeds. After McCleary and Matheson, 1975 [98]. (B) Changes in total a-galactosidase activity in germinated carob (x), lucerne ( ) and soybean (o) seeds. After McCleary and Matheson, 1974 [97]...

Fig. 22.4. Clinical approach to the diagnosis of Fabry disease. In affected females, a-galactosidase activity is often in the normal range. In those cases, the diagnosis has to be confirmed by mutation analysis.

Fig. 3. Comparison of transfection efficiencies obtained using PolyFect Reagent, a dendrimer-based transfection reagent, and a calcium phosphate-mediated procedure. COS-7 and HeLa cells were transfected in srx-weU plates with a /3-galactosidase expression plasmid using the appropriate protocol. For the calcium phosphate-mediated transfection, 6 pg of plasmid DNA was used and the medium was changed after 5 h incubation. Transfections were performed in triplicate, and transfection efficiency was measured by monitoring the /3-galactosidase activity of extracts obtained from the transfected cells. The amoimt of /3-galactosidase activity in the extracts correlates with the transfection efficiency. Cells were harvested 48 h post-trans-fection...

Extending the emulsion to a water-in-oil-in-water mixture allowed further refinement of the IVC concept. Compartmentalization of E. coli containing semm paraoxonase variants allowed the accumulation of fluorescent product to a point where it could be detected by FACS [57]. This approach was also used with in vitro transcription and translation to evolve /3-galactosidase activity from the Ebg gene [58]. 

S-galactosidase activity (Scheme 12) (201-203). Before the enzymatic cleavage, depending on the linker, the galactopyranose or a carbonate in bidentate coordination block the water access to the Gd111 ion. After enzymatic cleavage, one water molecule enters the inner sphere and results in an increased relaxivity. 

Thus, to summarize and to show that the two proteins interact, AH109 yeast cells transformed with the appropriate DNA-BD and AD vectors grow in -W, -L SD media and also in -W, -L, -H, -Ade SD media and yield a-galactosidase and p-galactosidase reporter gene activities. 

Escherichia coli cells grown in a medium with lactose as the only carbon source are monitored for p-galactosidase activity over time with the results shown below. 

Figure 3(A). Comparison of temperature optima for activities of glucose isomerase, amylase, and >galactosidase. Enzymes were assayed with cell extract from xylose-grown cells. A 100% activity value corresponds to 0.60, 0.58, and 0.46 U/mg for glucose isomerase, amylase, and -galactosidase, respectively. Cell extracts in 50 mM sodium phosphate buffer (pH 7.0), 100 mM sodium acetate buffer (pH 5.5), and 100 mM sodium phosphate buffer (pH 6.0) for glucose isomerase, amylase, and -galactosidase, respectively, were preincubatcd at the indicated temperatures, prior to the assay for residual enzyme activities. Reprinted with permission from ref. 20. Copyright 1990 American Society for Microbiology.

Fleet GWJ, Nicholas SJ, Smith PW, Evans SV, Fellows LE, Nash RJ. (1985) Potent competitive inhibition of a-galactosidase and a-glucosidase activity by l,4-dideoxy-l,4-iminopentitols Synthesis of l,4-dideoxy-l,4-imino-D-lyxitol and of both enantiomers of l,4-dideoxy-l,4-iminoarabinitol. 

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