| Title: | Functional characterizations of beta-glucosidases involved in aroma compound formation in tea (Camellia sinensis) |
| Author(s): | Zhou Y; Zeng L; Gui J; Liao Y; Li J; Tang J; Meng Q; Dong F; Yang Z; |
| Address: | "Guangdong Provincial Key Laboratory of Applied Botany, & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, China. Guangdong Provincial Key Laboratory of Applied Botany, & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China. Tea Research Institute, Guangdong Academy of Agricultural Sciences, & Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Dafeng Road 6, Tianhe District, Guangzhou 510640, China. College of Food Science, Southwest University, No. 2 Tiansheng Road, Beibei District, Chongqing 400715, China. Guangdong Food and Drug Vocational College, Longdongbei Road 321, Tianhe District, Guangzhou 510520, China. Guangdong Provincial Key Laboratory of Applied Botany, & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Xingke Road 723, Tianhe District, Guangzhou 510650, China; University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China. Electronic address: zyyang@scbg.ac.cn" |
| DOI: | 10.1016/j.foodres.2017.03.049 |
| ISSN/ISBN: | 1873-7145 (Electronic) 0963-9969 (Linking) |
| Abstract: | "Tea (Camellia sinensis) aroma is an important factor affecting tea quality. Many tea aroma compounds are present as glycosidically conjugated forms in tea leaves, and can be hydrolyzed by beta-glucosidase (beta-Glu) and beta-primeverosidase to release free tea aromas. beta-Primeverosidase has been identified and functionally characterized, while beta-Glu has not been identified in tea leaves. In the present study, we established a yeast expression system to recombine CsGH1BG1, CsGH3BG1, and CsGH5BG1, which belonged to GH1, GH3, and GH5 families in plants, respectively. These three recombinant Csbeta-Glus hydrolyzed the beta-glucopyranosidically conjugated aromas to form free aromas, suggesting that there was no specific Csbeta-Glus for the hydrolysis of beta-glucopyranosidically conjugated aromas in vitro. Furthermore, subcellular localization of the Csbeta-Glus indicated that CsGH1BG1 and CsGH3BG1 were located in the cytosol and vacuole, respectively, while CsGH5BG1 was located in the cell wall. This suggested that CsGH1BG1 and CsGH3BG1 might be responsible for the hydrolysis of beta-glucopyranosidically conjugated aromas in tea leaves during the tea manufacturing process. This study provides the first evidence of Csbeta-Glus in tea leaves, and will advance understanding of tea aroma formation" |
| Keywords: | Camellia sinensis/*enzymology/genetics Cellulases/genetics/*metabolism Glycosides/*metabolism Hydrolysis Isoenzymes *Odorants Plant Leaves/*enzymology Plant Proteins/genetics/*metabolism Substrate Specificity Volatile Organic Compounds/*metabolism (R)-1-p; |
| Notes: | "MedlineZhou, Ying Zeng, Lanting Gui, Jiadong Liao, Yinyin Li, Jianlong Tang, Jingchi Meng, Qing Dong, Fang Yang, Ziyin eng Research Support, Non-U.S. Gov't Canada 2017/05/22 Food Res Int. 2017 Jun; 96:206-214. doi: 10.1016/j.foodres.2017.03.049. Epub 2017 Apr 5" |
