DGGE和SSCP解析蔬菜类废物好氧降解过程细菌群落结构及演替的比较

Comparison of Using DGGE and SSCP to Characterize Bacterial Community and Dynamics During Aerobic Degradation of Vegetable Waste

针对细菌群落的16S rDNA V3区,采用2种DNA指纹图谱技术变性梯度凝胶电泳(DGGE)和单链构象多态性(SSCP),分析蔬菜类废物中温好氧降解过程中的细菌群落,比较2种技术对微生物群落结构和动态变化的解析水平。结果表明,指纹图谱显示细菌群落结构在中温好氧降解过程中有显著变化,随降解时间的延长总体呈现从简单到复杂的趋势;主成分分析对指纹图谱的解析结果表明,细菌群落结构的演替与好氧降解过程不同阶段生物质组成具有相关性。DGGE和SSCP两者提供的关于细菌群落结构及演替信息相似,但对演替过程的描述存在细微差异。DGGE较SSCP对细菌群落结构的微小变化更为敏感。

Two batches of mesophilic aerobic degradation of vegetable wastes were carried out to compare the resolutions of microbial communities and dynamics provided by denaturing gradient gel electrophoresis （DGGE） and single-strand conformation polymorphism （SSCP）. The comparison based on the V3 region of 16S rDNA gene of bacterial communities obtained from the different degradation phases, distinguished by the biomass composition of substrates. Significant changes were observed while attempting to reveal the microbial diversity and its succession during aerobic degradation with microbial diversity evolving from simple to complex, and the minor differences between two batches may be attributed to the different biomass composition of two vegetable wastes used. For the same sample, numbers of bands and peaks on respective profiles by DGGE and SSCP were comparable but slightly different indicating their similar resolutions on characterization of bacterial community structure. Principal component analysis （PCA） of fingerprinting profiles demonstrated that bacterial succession correlated with the biomass composition of vegetable wastes at different phases. With the proportion of low-degraded fractions （cellulose and lignin） increasing, the aerobic degradation could be divided into 3 phases, and PCA analysis of DGGE profiles presented 3 corresponding phases. However, PCA analysis of SSCP profiles only revealed 2 phases which was also reasonable because of the low degradation rate of lignin and cellulose. Hence DGGE and SSCP could provide similar information on bacterial community but slight differences on the resolution of bacterial succession. Comparing with SSCP, DGGE was more sensitive in detecting minor shift during bacterial succession.