Abstract:To explore the potential use of fruit tree in environmental renovation of phenolic compounds, we have cloned a polyphenol oxidase gene MdPPO2B from Malus Robusta and constructed a transgenic vector for over expressing this gene in plant. MdPPO2B was genetically transformed into the model plant Arabidopsis thaliana, and its function in degradation of phenolic compounds was analyzed. In solid MS, soil, liquid MS media without adding phenol, the morphology and growth status were indistinguishable between the transgenic and the wild type plants. However, when treated with the same media by adding 0.1 mM and 1 mM phenol respectively, MdPPO2B transgenic plants showed significantly enhanced tolerance to phenol compared to wild type. The root length and leave fresh weight of transgenic plants were longer and heavier than that of wild type plants. It indicates that the PPO activity, conferred by MdPPO2B, is highly required for degrading of phenol in transgenic Arabidopsis. This work suggests that many fruit-derived genes may be good candidate for phytoremediation of pollutants in the environment.