Localization and Characterization of α-Glucosidase Activity in Lactobacillus brevis

Abstract

Lactobacillus brevis is found together with the yeast Brettanomyces lambicus during the overattenuation process in spontaneously fermented Iambic beer. An isolated L. brevis strain has been shown to produce an a-glucosidase with many similarities to the glucosidase earlier found in B. lambicus. The enzyme was purified by ammonium sulfate precipitation, gel (Sephadex G-150 and Ultrogel AcA-44) filtration, and ion-exchange chromatography (DEAE-Sephadex A-50). The molecular weights of the enzyme, as determined by gel chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were about 50,000 and 60,000, respectively. Optimum catalytic activity was obtained at 40°C and pH 6.0. The enzyme showed a decrease of hydrolysis with an increase in the degree of polymerization of the substrate. The Km values for p-nitrophenyla-D-glucopyranoside, maltose, and maltotriose were 0.51, 3.0, and 5.2 mM, respectively. There was lack of inhibition by 0.15 mM acarbose and 0.5 M turanose, but the enzyme was inhibited by Tris (Ki value of 25 mM). The ot-glucosidase of L. brevis together with the enzyme of B. lambicus seems to be a key factor in the overattenuation of lambic beer, although the involvement of other lactic acid bacteria (pediococci) cannot be excluded.

Metabolic Profiling of Xylooligosaccharides by Lactobacilli

“…Lb. brevis is involved in the natural fermentation of hemicellulose-rich plant food/feed (e.g., cabbage, sourdough, and forage silage), and despite the aspects mentioned below, it is also an important starter organism for the “over-attenuation” process used to produce several beer varieties [ 43 , 44 , 45 ]. However, next to Pediococcus spp., obligately heterofermentative Lactobacillus spp.…”

Genetic and biochemical characterization of an oligo-α-1,6-glucosidase from Lactobacillus plantarum

“…These include: 1) a β-galactosidase, an enzyme involved both in the development of L. plantarum in milk and dairy products (Mayo et al, 1994) and in the synthesis of galactooligosaccharides from lactose (Iqbal et al, 2010); 2) two αgalactosidases involved in the catabolism of plant-derived α-galactosides (Acebrón et al, 2009;Silvestroni et al, 2002); 3) two α-rhamnosidases that catalyze the hydrolysis of rhamnosides containing α-glycosidic bonds (Ávila et al, 2009); 4) an amylopullulanase found in starch-hydrolyzing L. plantarum strains (Kim et al, 2008;Olympia et al, 1995); and 5) a β-glucosidase, which might in wine contribute to the release of flavour compounds from odourless β-glucoside and di-glucoside conjugates (Spano et al, 2005). Though α-glucosidase activity has been shown in Lactobacillus spp., such as Lactobacillus acidophilus (Li and Chan, 1983) and Lactobacillus brevis (De Cort et al, 1994), the -glucosidases of lactobacilli have been very little studied.…”

“…The -glucosidases of Lactobacillus have been little studied (Gänzle and Follador, 2012) compared to other glycosidases. Nonetheless, -glucosidase activity has been reported for whole cells and cell-free extracts of Lactobacillus acidophilus (Li and Chang, 1983), and an intracellular -glucosidase has been purified and characterized from Lactobacillus brevis isolated from lambic beer (de Cort et al, 1994). More recently, -glucosidases from Lactobacillus johnsonii (Kang et al, 2009) and Lactobacillus acidophilus (Møller et al, 2012) have been characterized at the biochemical and genetic level.…”

Basic characterization and partial purification of β-glucosidase from cell-free extracts of Oenococcus oeni ST81

“…A protocol according to De Cort et al (1994) partially modified by Michlmayr et al (2010a) was followed to determine the cellular localization of the enzyme. The washed cells were resuspended in 0AE5 mol l )1 sodium malate buffer, pH 6AE0 (isotonic buffer) up to an absorbance at 600 nm of 4, and treated with different concentrations of lysozyme (Sigma, c. 55 000 U mg )1 ) for 30 min at 37°C.…”