Isolation and Identification of a Phyllospheric Yeast Strain Capable of Utilizing BDE-3 as Sole Carbon and Energy Source

Abstract

As a class of synthetic organic compounds widely used in varieties of industrial products, polybrominated diphenyl ethers (PBDEs) have attracted increasing attention for the properties of toxicity, bioaccumulation and persistence. In this paper, the phyllospheric yeast strain capable of aerobic degradation of 4-brominated diphenyl ether (BDE-3) was originally isolated from Populus tomentosa. Based on the morphological properties and the ITS sequence analysis, the obtained yeast was identified as Wickerhamomyces anomalus and designated Y1. The endurance ability of Y1 to BDE-3 exposure was determined by BDE-3 concentration gradient experiment. BDE-3 removal efficiency analysis was conducted by applying GC-μECD with initial BDE-3 content of 40 mg/L. Results showed Y1 could remove 83.58±2.60% of 40 mg/L BDE-3 in 3-day aerobic incubation. The tolerance range of pH and NaCl concentration were determined for further engineering application. It could be the first report about PBDEs degradation by yeast strain, isolated from the phyllosphere of P. tomentosa at the non-contaminated site of a subastral ecological niche, and might be advantageous in comprehensive exploitation of phytoremediation.