Characterization of the recombinant Brettanomyces anomalus β-glucosidase and its potential for bioflavouring.
OBJECTIVE
Plant materials used in the food industry contain up to five times more aromas bound to glucose (glucosides) than free, unbound aromas, making these bound aromas an unused flavouring potential. The aim of this study was to identify and purify a novel β-glucosidase from Brettanomyces yeasts that are capable of releasing bound aromas present in various food products.


RESULTS
We screened 428 different yeast strains for β-glucosidase activity and are the first to sequence the whole genome of two Brettanomyces yeasts (Brettanomyces anomalus and Brettanomyces bruxellensis) with exceptionally high β-glucosidase activity. Heterologous expression and purification of the identified B. anomalus β-glucosidase showed that it has an optimal activity at a higher pH (5·75) and lower temperature (37°C) than commercial β-glucosidases. Adding this B. anomalus β-glucosidase to cherry beers and forest fruit milks resulted in increased amounts of benzyl alcohol, eugenol, linalool and methyl salicylate compared to Aspergillus niger and Almond glucosidase.


CONCLUSIONS
The newly identified B. anomalus β-glucosidase offers new possibilities for food bioflavouring.


CONCLUSIONS
This study is the first to sequence the B. anomalus genome and to identify the β-glucosidase-encoding genes of two Brettanomyces species, and reports a new bioflavouring enzyme.
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
Y
Y
Vervoort
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
B
B
Herrera-Malaver
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
S
S
Mertens
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
V
V
Guadalupe Medina
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
J
J
Duitama
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
L
L
Michiels
Leuven Food Science and Nutrition Research Centre, Leuven, Belgium.
G
G
Derdelinckx
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
K
K
Voordeckers
VIB Laboratory of Systems Biology, Leuven, Belgium.|CMPG Laboratory for Genetics and Genomics, KU Leuven, Leuven, Belgium.
K J
KJ
Verstrepen
D055168:Brettanomyces / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D005285:Fermentation; D005421:Flavoring Agents / Q000032:analysis / Q000378:metabolism*; D005516:Food Microbiology; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D027861:Prunus / Q000378:metabolism / Q000382:microbiology; D001617:beta-Glucosidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D005421:Flavoring Agents; D005656:Fungal Proteins; D001617:beta-Glucosidase
Brettanomyces; enzyme; flavours; yeast; β-glucosidase