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Molecular Characterization and Genetic Expression Profiles of Two Glycosidases from Different Oenococcus oeni Strains

Ji-Feng Wang, Shi-Ling Yang, Qiang Meng, Shu-Wen Liu and Ling He

The aim of this study was to characterize β-glycosidase (BGL) andphospho-β-glycosidase (PBGL), which is responsible for the oenological aromatic characteristics of wines. Six Oenococcus oeni strains were evaluated for their enzymatic activities by using p-nitrophenyl-β-D-glucopyranoside (pNPG) method. The sequences of BGL and PBGL genes were analyzed by bioinformatics techniques and validated by quantitative real-time reverse transcription polymerase chain reaction technology (qRT-PCR). The genetic codes of wine-related β-glycosidases in the O. oeni were also analyzed to compare with the other strains. It was found that O. oeni CS-1b displayed the highest activity among all the strains. The enzymatic activity was high in the disrupted cell solution but low in the supernatants obtained from the intact cultured strain. It indicated that glycosidases were possibly mainly in cell-bound or intracellular form in those strains. The results of GC-MS showed that strains CS-1b and SD-1f which have higher level of gene expression can produce more kinds of aromas and some of them related to β-glucosidase were significantly increased.