Purification and characterization of invertase from Lactobacillus reuteri CRL 1100.
The invertase of Lactobacillus reuteri CRL 1100 is a glycoprotein composed by a single subunit with a molecular weight of 58 kDa. The enzyme was stable below 45 degrees C over a wide pH range (4.5-7.0) with maximum activity at pH 6.0 and 37 degrees C. The invertase activity was significantly inhibited by bivalent metal ions (Ca(++), Cu(++), Cd(++), and Hg(++)), beta-mercaptoethanol, and dithiothreitol and partially improved by ethylenediaminetetraacetic acid. The enzyme was purified 32 times over the crude extract by gel filtration and ion-exchange chromatography with a recovery of 17%. The K(m) and V(max) values for sucrose were 6.66 mM and 0.028 micromol/min, respectively. An invertase is purified and characterized for the first time in Lactobacillus, and it proved to be a beta-fructofuranosidase.
Cuezzo de Ginés
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Cátedra de Bioquímica Clínica III, Universidad Nacional de Tucumán, Argentina.
Maldonado
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Font de Valdez
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D002852:Chromatography, Ion Exchange; D004795:Enzyme Stability; D006026:Glycoside Hydrolases / Q000302:isolation & purification* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007778:Lactobacillus / Q000201:enzymology*; D013379:Substrate Specificity; D013395:Sucrose / Q000378:metabolism; D013696:Temperature; D043324:beta-Fructofuranosidase
D013395:Sucrose; D006026:Glycoside Hydrolases; D043324:beta-Fructofuranosidase