https://www.abbs.info
E-mail: [email protected]
ISSN
1672-9145
Acta Biochim Biophys Sin
2005, 37(6): 363–370
CN 31-1940/Q
Purification and Partial Characterization of b-Glucosidase
from Fresh Leaves of Tea Plants (Camellia sinensis (L.) O.
Kuntze)
Ye-Yun LI, Chang-Jun JIANG*,
Xiao-Chun WAN, Zheng-Zhu ZHANG, and Da-Xiang LI
Key Laboratory of Tea Biochemistry and Biotechnology, Ministry of
Education, Anhui Agricultural University, Hefei 230036, China
Abstract b-Glucosidases are important
in the formation of floral tea aroma and the development of resistance to
pathogens and herbivores in tea plants. A novel b-glucosidase was purified
117-fold to homogeneity, with a yield of 1.26%, from tea leaves by chilled
acetone and ammonium sulfate precipitation, ion exchange chromatography
(CM-Sephadex C-50) and fast protein liquid chromatography (FPLC; Superdex 75,
Resource S). The enzyme was a monomeric protein with specific activity of 2.57
U/mg. The molecular mass of the enzyme was estimated to be about 41 kDa and 34
kDa by SDS-PAGE and FPLC gel filtration on Superdex 200, respectively. The
enzyme showed optimum activity at 50 °C and was stable at temperatures lower
than 40 °C. It was active between pH 4.0 and pH 7.0, with an optimum activity
at pH 5.5, and was fairly stable from pH 4.5
to pH 8.0. The enzyme showed maximum activity towards pNPG, low activity
towards pNP-Galacto, and no activity towards pNP-Xylo.
Key words Camellia sinensis;
b-glucosidase;
purification; characterization
—————–
Received: December 29,
2004
Accepted: March 29, 2005
This work was supported by grants from the Key Natural Science
Research Program of the Department of Education of Anhui Province (No.
2004kjl37zd) and the Key Program of Science and Technique Research of the
Ministry of Education of China (No. 00182)
*Corresponding author: Tel, 86-551-5156265; Fax,
86-551-5156265; E-mail, [email protected]