O Galactosidase

In order to account for the inability of many enzymes to bind the protonated form of the basic inhibitors or permanently cationic ones better than uncharged analogs (for example, yS-o-galactosidase from E. coli, and P-v>-glucosidase from almonds), it was proposed that the enzyme could proton-ate the inhibitor at the active site by a cationic acid (for example, protonated histidine). If proton transfer cannot occur, the attractive forces due to the carboxylate would be canceled by the repulsion from the cationic acid. Experimental evidence for this proposal is, however, still lacking. In fi-D-gn-lactosidase from E. coli, a tyrosine is presumed to be responsible for the protonation of substrates. ... 

Rossi, F., Charlton, C. A., and Blau, H. M. (1997). Monitoring protein-protein interactions in intact eukaryotic cells by O-galactosidase complementation. Proc. Natl. Acad. Sci. USA 94, 8405-8410. 

Calystegine Ni weak inhibitor of disaccharidase-type a-glucosidases and potent inhibitor of P-glucosidases (including cellobiase), lactase and o-galactosidase ... 

Bio-imprinting of enzymes to enhance their enantioselectivity is thus fairly established. This is particularly useful for enzymes which inherently offer low enantioselectivity, e.g. lipases. Okahata and co-workers established that lipid coating of lipases enhances the solubility of the enzymes in organic media [24]. Subsequently, the technique was extended to phospholipase D for transphosphotidylation of water insoluble phospholipids in organic solvents and to jS-o-galactosidase for the... 

The relationship between the a-o-fucosidase and a-o-galactosidase activities in human and animal tissues, etc., has been investigated. ... 

Purification of p-o-galactosidase Isolation of the apo-form of ovoflavoprotein Isolation of P-lactamases Purification of a cysteine-containing histone Separation of the principal glycoproteins in human red-cell membranes from other proteins Purification of corticosteroid-binding globulin Purification of transcortin Separation of membrane-bound enzymes Studies of the effect of the chain-length on the adsorption 125 of albumin removal of albumin from sera... 

The leakage of immobilized p-o-fructofuranosidase, p-o-galactosidase, and glucoamylase from gels of poly(2-hydroxyethyl acrylate) or polydimethylacryl-amide has been studied.p-o-Fructofuranosidase and a-o-glucosidase immobilized within hollow fibres showed no detectable leakage and, when the fibres were pretreated with albumin, the stabilities of the immobilized enzymes approached those of the free enzymes. ... 

The interaction of an alkali-stable polysaccharide from the cell surface of staphylococci with human fibrinogen has been modified by prior treatment of the polysaccharide with D-glucose oxidase, a-o-galactosidase, or jS-o-2-acetamido-2-deoxyglucosidase,... 

It has been shown that the a-D-galactosidase B from human liver also exhibits a-D-2-acetamido-2-deoxygalactosidase activity (p. 392). A highly purified fraction of a-o-galactosidase B from human liver was found to contain a-D-2-acetamido-2-deoxygalactosidase activity (Am 2-nitrophenyl 2-acetamido-2-deoxy-a-D-galactopyranoside 1.3 mM, Am 4-methylumbelliferyl a-D-galacto-pyranoside 6.8 mM). The hydrolysis of the latter substrate was completely... 

The conversion of /S-o-galactosidase (lactase)-hydrolysed acid whey to alcohol has been reported. ... 

Two forms of initiation factor 2 (mol. wt. 9.0 x 10 ) have been isolated from E. coli extracts and tested for their ability to support j8-o-galactosidase biosynthesis in a phage DNA-directed in vitro protein biosynthesis system. Only the IF-2a form was found to function in jS-o-galactosidase biosynthesis. 

Tissues from a case of juvenile (type 3) Gaucher disease exhibited a deficiency of j8-D-glucosidase activity. Evidence was presented for the manifestation of jS-D-glucosidase, /S-o-galactosidase, and j8-D-xylosidase activities by a single enzyme species. 

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