Glycosidase activity

G. W. J. Fleet, An alternative proposal for die mode of inhibition of glycosidase activity by polyhydroxylated piperidines, pyrrolidines and indolizidines Implications for the mechanism of action of some glycosidases, Tetrahedron Lett., 26 (1985) 5073—5076. 

Beighton. Inhibition of peptidase and glycosidase activities of Porphyromonas gingivalis, Bacteroid.es intermedius and... 

The following kinds of observation have provided evidence of external glycosidase activity. (i) The idea of similarity of activity in vivo and in vitro has long been recognized for example, by von Euler and Kullberg39 in 1911. The effect, on the glycosidase activity of intact cells, of varying the pH is the same as that for the enzyme in solution (see Fig. l).4°a3-45 Inhibitors of transport across the plasmalemma,... 

RIPs are plant protein toxins that are able to inhibit enzymatically ribosomal activity and are therefore highly cytotoxic [98]. RIPs are taken up in the cells by means of endocytosis, and only a small fraction (5% or less) are translocated to the cytosol where the toxins inhibit the protein synthesis and eventually kill the cell. PCI may be used to increase both the efficacy and specificity of these toxins. RIPs are divided into two groups, type I and type II. Type II RIPs, like ricin, consists of two polypeptide chains, one cytotoxic A-chain with /V-glycosidase activity and one B-chain which binds to the cell surface. Type I RIPs, like gelonin, agrostin, and saporin, lack the B chain, which make them poorly transported over the cell- and intracellular membranes to the cell cytosol. Hence, the cytotoxic effect of these protein toxins is usually absent or very low. A considerable cytotoxic effect of type I RIPs has been shown in combination with PCI, both in vitro and in vivo [25, 99]. 

Endo, Y. and Tsurugi, K. (1987) RNA N-glycosidase activity of ricin A-chain. Mechanism of action of the toxic lectin ricin on eukaryotic ribosomes. J. Biol. Chem. 262, 8128-8130. 

Vocadlo DJ, Bertozzi CR (2004) A strategy for functional proteomic analysis of glycosidase activity from cell lysates. Angew Chem Int Ed Engl 43 5338-5342... 

Antibodies possessing glycosidase activity have been induced by immunization of mice with conjugates of the transition-state analogue 21 (Fig. 5.10A). A combinatorial phage-Fab library was then constructed by PCR amplification of the heavy and light chains. Selection with a BSA-conjugated suicide inhibitor 22 (Fig. 5.10B) was then... 

The conditions for enzymatic analysis varied with the enzyme under study. In general, the reactions were started by the addition of the enzyme activity, and incubations were at 37°C. The reaction was stopped by the addition of 100% methanol, and precipitated protein was removed by centrifugation. Samples of the supernatant solution were analyzed by HPLC. A chromatogram of a glycosidase activity is shown in Figure 9.74. The peak of free 4-MU is noted. The enzyme was obtained from urine samples. 

The release of glycosidically-bound aroma compounds, such as monoterpenes, C13 norisoprenoids, and aliphatic alcohols, can be achieved by the action of glycosi-dase enzymes. 3-Glycosidase activity has not been much studied in wine LAB. McMahon et al. (1999) detected a low p-glycosidase activity in O. oeni OSU and a... 

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