title: An alkaline β-glucosidase isolated from an olive brine strain of Wickerhamomyces anomalus.
abstract: An efficient β-glucosidase (βG)-producing strain, Wickerhamomyces anomalus BS81, was isolated from naturally fermented olive brine and identified based on PCR/restriction fragment length polymorphism of the rDNA internal transcribed spacer and sequence analysis of the D1/D2 region of the 26S rRNA gene. The hydrolytic activity of the βG had an optimum pH of 8.5 and an optimum temperature of 35 °C. The enzyme had high substrate specificity and high catalytic efficiency (K(m) 0.99 mM, V(max) 14 U g(-1) of cells) for p-nitrophenyl-β-d-glucopyranoside. The enzyme was activated by increasing concentrations of NaCl, with maximum activity at 150 g L(-1) NaCl. Although βGs have been purified and characterized from several other sources, the W. anomalusβG is unique among βGs because its relative maximum activity occurs at alkaline pH and 35 °C. Moreover, the yeast strain has esterase activity that acts synergistically with βG to degrade oleuropein to debitter table olives and olive oil.
authors.affiliation: DISPA - Sezione di Tecnologia e Microbiologia degli Alimenti, University of Catania, Italy. crestu@unict.it
authors.forename: Cristina
authors.initials: C
authors.lastname: Restuccia
authors.forename: Serena
authors.initials: S
authors.lastname: Muccilli
authors.forename: Rosa
authors.initials: R
authors.lastname: Palmeri
authors.forename: Cinzia L
authors.initials: CL
authors.lastname: Randazzo
authors.forename: Cinzia
authors.initials: C
authors.lastname: Caggia
authors.forename: Giovanni
authors.initials: G
authors.lastname: Spagna
mesh_terms: D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D020536:Enzyme Activators / Q000378:metabolism; D004795:Enzyme Stability; D005960:Glucosides / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D031658:Olea / Q000382:microbiology; D012335:RNA, Ribosomal / Q000235:genetics; D004718:Saccharomycetales / Q000145:classification* / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature; D001617:beta-Glucosidase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D020536:Enzyme Activators; D005960:Glucosides; D012335:RNA, Ribosomal; C065096:RNA, ribosomal, 26S; C025193:4-nitrophenyl beta-D-glucoside; D012965:Sodium Chloride; D001617:beta-Glucosidase