Prokaryotic expression of polyphenol oxidase mature protein from Camellia sinensis.

Camellia sinensis polyphenol oxdiase (PPO) plays essential roles in the quality formation of tea processing. Despite that it always is a hotspot, there is no report on expressing C. sinensis PPO in vitro. Based on purifying the active Yihongzao PPO with transit-peptide expressed in Escherichia coli, the active mature form was also expressed in E. coli and purified from the inclusion bodies. The specific activity of the mature form was higher about three times than that of PPO with transit-peptide, which suggests that the transit-peptide should restrain the activity of PPO in vivo and in vitro. It is helpful to yield and apply for the C. sinensis engineering PPO with high activity in a large-scale.