Screening of a salt-tolerant PHE-degrading bacterium and its physiological response to salt stresses
Through the high-throughput screening technique,a highly effective phenanthrene-degrading bacterium was screened and i-solated from the oil sludge of the Shengli Oilfield,China.By means of 16S rDNA sequencing,the strain was identified as Pseudar-throbacter phenanthrenivorans and named as A-5.Physiological responses of strain A-5 were investigated in the face of different levels of salt stresses(with 0,1%,3%,5%and 7%NaCl added,respectively).The results showed that the strain A-5 exhibited a high degra-dation capacity of phenanthrene under salinities of less than 3%,with a weekly degradation rate of 95.45%,91.20%and 79.54%,re-spectively.However,when added NaCl above 5%,its degradation efficiency decreased significantly to 2.98%and 1.56%,respectively.The growth rate of strain A-5 was gradually inhibited with the increase of LB medium salinity.When the ambient salinity increased,contents of saturated fatty acids in cell membrane of strain A-5 decreased,while the contents of unsaturated fatty acids and the intracel-lular ectoine increased.
万方数据
维普
