PCR-DGGE Analysis of Microbial Community during Bioleaching Process of Waste Printed Wire Boards by Acidophilic Bacteria
嗜酸性细菌浸出废旧线路板过程中微生物群落的聚合酶链式反应变性梯度凝胶电泳分析

The mixed culture of acidophilic bacteria was used as the inoculant to bioleach waste printed wire boards.Meanwhile,bacteria in different leaching phases(0,5,24 and 60 h) were sampled,and denaturing gradient gel electrophoresis(DGGE) analysis of polymerase chain reaction(PCR)-amplified 16Sr RNA genes was used to evaluate the change of microbial community structure during the bioleaching process.The results showed that the mixed culture of acidophilic bacteria could bioleach 96.36 % copper from the boards in 48 h.The analysis of the bands selected from the DGGE gel revealed that the sequences of seven bands(Z1~Z7) had over 99% sequence similarity with Acidithiobacillus ferrooxidans.It meant that the seven strains were all clustered to Acidithiobacillus ferrooxidans genus.The relative abundance of Z1 to Z7 in the four samples was not changed significantly.Meanwhile,Z3 showed the highest relative abundance during the whole bioleaching process,which was 72.70%,82.90%,79.00% and 85.80%,respectively.Therefore,the microbial community structure changed a little bit during the bioleaching,which always consisted of Acidithiobacillus ferrooxidans strains and was dominated by strain Z3.